trunk/Documentation/lscp.xml

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    <front>
        <title>LinuxSampler Control Protocol</title>
        <author initials='C.S.' surname="Schoenebeck" fullname='C.
Schoenebeck'>
            <organization>
                Interessengemeinschaft Software Engineering e. V.
            </organization>
            <address>
                <postal>
                    <street>Max-Planck-Str. 39</street>
<!--                    <code>74081</code> -->
                    <city>74081 Heilbronn</city>
                    <country>Germany</country>
                </postal>
                <email>schoenebeck at software minus engineering dot org</email>
            </address>
        </author>
        <date month="November" year="2006"/>
        <workgroup>LinuxSampler Developers</workgroup>
        <keyword>LSCP</keyword>
        <abstract>
            <t>The LinuxSampler Control Protocol (LSCP) is an
            application-level protocol primarily intended for local and
            remote controlling the LinuxSampler backend application, which is a
            sophisticated server-like console application essentially playing
            back audio samples and manipulating the samples in real time to
            certain extent.</t>
        </abstract>
    </front>

    <middle>
        <section title="Requirements notation">
            <t>The key words "MUST", "MUST NOT", "REQUIRED", "SHALL",
            "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY",
            and "OPTIONAL" in this document are to be interpreted as
            described in <xref target="RFC2119"/>.</t>

            <t>This protocol is always case-sensitive if not explicitly
            claimed the opposite.</t>

            <t>In examples, "C:" and "S:" indicate lines sent by the client
            (front-end) and server (LinuxSampler) respectively. Lines in
            examples must be interpreted as every line being CRLF
            terminated (carriage return character followed by line feed
            character as defined in the ASCII standard), thus the following
            example:</t>

            <t>
                <list>
                    <t>C: "some line"</t>
                    <t>&nbsp;&nbsp;&nbsp;"another line"</t>
                </list>
            </t>

            <t>must actually be interpreted as client sending the following
            message:</t>

            <t>
                <list>
                    <t>"some line&lt;CR&gt;&lt;LF&gt;another
                    line&lt;CR&gt;&lt;LF&gt;"</t>
                </list>
            </t>

            <t>where &lt;CR&gt; symbolizes the carriage return character and
            &lt;LF&gt; the line feed character as defined in the ASCII
            standard.</t>

            <t>Due to technical reasons, messages can arbitrary be
            fragmented, means the following example:</t>

            <t>
                <list>
                    <t>S: "abcd"</t>
                </list>
            </t>

            <t>could also happen to be sent in three messages like in the
            following sequence scenario:</t>

            <t>
                <list style="symbols">
                    <t>server sending message "a"</t>
                    <t>followed by a delay (pause) with
                    arbitrary duration</t>
                    <t>followed by server sending message
                    "bcd&lt;CR&gt;"</t>
                    <t>again followed by a delay (pause) with arbitrary
                    duration</t>
                    <t>followed by server sending the message
                    "&lt;LF&gt;"</t>
                </list>
            </t>

            <t>where again &lt;CR&gt; and &lt;LF&gt; symbolize the carriage
            return and line feed characters respectively.</t>
        </section>

        <section title="Versioning of this specification" anchor="LSCP versioning">
            <t>LSCP will certainly be extended and enhanced by-and-by. Each official
            release of the LSCP specification will be tagged with a unique version
            tuple. The version tuple consists at least of a major and minor version
            number like:
            </t>
            <t>
                <list>
                    <t>"1.2"</t>
                </list>
            </t>
            <t>
            In this example the major version number would be "1" and the minor
            version number would be "2". Note that the version tuple might also
            have more than two elements. The major version number defines a
            group of backward compatible versions. That means a frontend is
            compatible to the connected sampler if and only if the LSCP versions
            to which each of the two parties complies to, match both of the
            following rules:
            </t>
            <t>Compatibility:</t>
            <t>
                <list style="numbers">
                    <t>The frontend's LSCP major version and the sampler's LSCP
                    major version are exactly equal.</t>
                    <t>The frontend's LSCP minor version is less or equal than
                    the sampler's LSCP minor version.</t>
                </list>
            </t>
            <t>
            Compatibility can only be claimed if both rules are true.
            The frontend can use the
            <xref target="GET SERVER INFO">"GET SERVER INFO"</xref> command to
            get the version of the LSCP specification the sampler complies with.
            </t>
        </section>

        <section title="Introduction">
            <t>LinuxSampler is a so called software sampler application
            capable to playback audio samples from a computer's Random
            Access Memory (RAM) as well as directly streaming it from disk.
            LinuxSampler is designed to be modular. It provides several so
            called "sampler engines" where each engine is specialized for a
            certain purpose. LinuxSampler has virtual channels which will be
            referred in this document as "sampler channels". The channels
            are in such way virtual as they can be connected to an
            arbitrary MIDI input method and arbitrary MIDI channel (e.g.
            sampler channel 17 could be connected to an ALSA sequencer
            device 64:0 and listening to MIDI channel 1 there). Each sampler
            channel will be associated with an instance of one of the available
            sampler engines (e.g. GigEngine, DLSEngine). The audio output of
            each sampler channel can be routed to an arbitrary audio output
            method (ALSA / JACK) and an arbitrary audio output channel
            there.</t>
        </section>

        <section title="Focus of this protocol">
            <t>Main focus of this protocol is to provide a way to configure
            a running LinuxSampler instance and to retrieve information
            about it. The focus of this protocol is not to provide a way to
            control synthesis parameters or even to trigger or release
            notes. Or in other words; the focus are those functionalities
            which are not covered by MIDI or which may at most be handled
            via MIDI System Exclusive Messages.</t>
        </section>

        <section title="Communication Overview">
            <t>There are two distinct methods of communication between a
            running instance of LinuxSampler and one or more control
            applications, so called "front-ends": a simple request/response
            communication method used by the clients to give commands to the
            server as well as to inquire about server's status and a
            subscribe/notify communication method used by the client to
            subscribe to and receive notifications of certain events as they
            happen on the server. The latter needs more effort to be
            implemented in the front-end application. The two communication
            methods will be described next.</t>

            <section title="Request/response communication method">
                <t>This simple communication method is based on
                <xref target="RFC793">TCP</xref>. The
                front-end application establishes a TCP connection to the
                LinuxSampler instance on a certain host system. Then the
                front-end application will send certain ASCII based commands
                as defined in this document (every command line must be CRLF
                terminated - see "Conventions used in this document" at the
                beginning of this document) and the LinuxSampler application
                will response after a certain process time with an
                appropriate ASCII based answer, also as defined in this
                document. So this TCP communication is simply based on query
                and answer paradigm. That way LinuxSampler is only able to
                answer on queries from front-ends, but not able to
                automatically send messages to the client if it's not asked
                to. The fronted should not reconnect to LinuxSampler for
                every single command, instead it should keep the connection
                established and simply resend message(s) for subsequent
                commands. To keep information in the front-end up-to-date
                the front-end has to periodically send new requests to get
                the current information from the LinuxSampler instance. This
                is often referred to as "polling". While polling is simple
                to implement and may be OK to use in some cases, there may
                be disadvantages to polling such as network traffic overhead
                and information being out of date.
                It is possible for a client or several clients to open more
                than one connection to the server at the same time. It is
                also possible to send more than one request to the server
                at the same time but if those requests are sent over the
                same connection server MUST execute them sequentially. Upon
                executing a request server will produce a result set and
                send it to the client. Each and every request made by the
                client MUST result in a result set being sent back to the
                client. No other data other than a result set may be sent by
                a server to a client. No result set may be sent to a client
                without the client sending request to the server first. On
                any particular connection, result sets MUST be sent in their
                entirety without being interrupted by other result sets. If
                several requests got queued up at the server they MUST be
                processed in the order they were received and result sets
                MUST be sent back in the same order.</t>

                <section title="Result format">
                    <t>Result set could be one of the following types:</t>
                    <t>
                        <list style="numbers">
                            <t>Normal</t>
                            <t>Warning</t>
                            <t>Error</t>
                        </list>
                    </t>
                    <t>Warning and Error result sets MUST be single line and
                    have the following format:</t>
                    <t>
                        <list style="symbols">
                   <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;"</t>
                   <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;"</t>
                        </list>
                    </t>
                    <t>Where &lt;warning-code&gt; and &lt;error-code&gt; are
                    numeric unique identifiers of the warning or error and
                    &lt;warning-message&gt; and &lt;error-message&gt; are
                    human readable descriptions of the warning or error
                    respectively.</t>
                    <t>Examples:</t>
                    <t>
                        <list>
                            <t>C: "LOAD INSTRUMENT '/home/me/Boesendorfer24bit.gig" 0 0</t>
                            <t>S: "WRN:32:This is a 24 bit patch which is not supported natively yet."</t>
                        </list>
                    </t>
                    <t>
                        <list>
                            <t>C: "GET AUDIO_OUTPUT_DRIVER_PARAMETER INFO ALSA EAR"</t>
                            <t>S: "ERR:3456:Audio output driver 'ALSA' does not have a parameter 'EAR'."</t>
                        </list>
                    </t>
                    <t>
                        <list>
                            <t>C: "GET AUDIO_OUTPUT_DEVICE INFO 123456"</t>
                            <t>S: "ERR:9:There is no audio output device with index 123456."</t>
                        </list>
                    </t>
                    <t>Normal result sets could be:</t>
                    <t>
                        <list style="numbers">
                            <t>Empty</t>
                            <t>Single line</t>
                            <t>Multi-line</t>
                        </list>
                    </t>
                    <t> Empty result set is issued when the server only
                    needed to acknowledge the fact that the request was
                    received and it was processed successfully and no
                    additional information is available. This result set has
                    the following format:</t>
                    <t>
                        <list>
                            <t>"OK"</t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "SET AUDIO_OUTPUT_DEVICE_PARAMETER 0 CHANNELS=4"</t>
                            <t>S: "OK"</t>
                        </list>
                    </t>
                    <t>Single line result sets are command specific. One
                    example of a single line result set is an empty line.
                    Multi-line result sets are command specific and may
                    include one or more lines of information. They MUST
                    always end with the following line:</t>
                    <t>
                        <list>
                            <t>"."</t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "GET AUDIO_OUTPUT_DEVICE INFO 0"</t>
                            <t>S: "DRIVER: ALSA"</t>
                            <t>&nbsp;&nbsp;&nbsp;"CHANNELS: 2"</t>
                            <t>&nbsp;&nbsp;&nbsp;"SAMPLERATE: 44100"</t>
                            <t>&nbsp;&nbsp;&nbsp;"ACTIVE: true"</t>
                            <t>&nbsp;&nbsp;&nbsp;"FRAGMENTS: 2"</t>
                            <t>&nbsp;&nbsp;&nbsp;"FRAGMENTSIZE: 128"</t>
                            <t>&nbsp;&nbsp;&nbsp;"CARD: '0,0'"</t>
                            <t>&nbsp;&nbsp;&nbsp;"."</t>
                        </list>
                    </t>
                    <t>In addition to above mentioned formats, warnings and
                    empty result sets MAY be indexed. In this case, they
                    have the following formats respectively:</t>
                    <t>
                        <list style="symbols">
                            <t>"WRN[&lt;index&gt;]:&lt;warning-code&gt;:&lt;warning-message&gt;"</t>
                            <t>"OK[&lt;index&gt;]"</t>
                        </list>
                    </t>
                    <t>where &lt;index&gt; is command specific and is used
                    to indicate channel number that the result set was
                    related to or other integer value.</t>
                    <t>Each line of the result set MUST end with
                    &lt;CRLF&gt;.</t>
                    <t>Examples:</t>
                    <t>
                        <list>
                            <t>C: "ADD CHANNEL"</t>
                            <t>S: "OK[12]"</t>
                        </list>
                    </t>
                    <t>
                        <list>
                            <t>C: "CREATE AUDIO_OUTPUT_DEVICE ALSA SAMPLERATE=96000"</t>
                            <t>S: "WRN[0]:32:Sample rate not supported, using 44100 instead."</t>
                        </list>
                    </t>
                </section>
            </section>
            <section title="Subscribe/notify communication method">
                <t>This more sophisticated communication method is actually
                only an extension of the simple request/response
                communication method. The front-end still uses a TCP
                connection and sends the same commands on the TCP
                connection. Two extra commands are SUBSCRIBE and UNSUBSCRIBE
                commands that allow a client to tell the server that it is
                interested in receiving notifications about certain events
                as they happen on the server. The SUBSCRIBE command has the
                following syntax:</t>

                <t>
                    <list>
                        <t>SUBSCRIBE &lt;event-id&gt;</t>
                    </list>
                </t>

                <t>where &lt;event-id&gt; will be replaced by the respective
                event that client wants to subscribe to. Upon receiving such
                request, server SHOULD respond with OK and start sending
                EVENT notifications when a given even has occurred to the
                front-end when an event has occurred. It MAY be possible
                certain events may be sent before OK response during real
                time nature of their generation. Event messages have the
                following format:</t>

                <t>
                    <list>
                        <t>NOTIFY:&lt;event-id&gt;:&lt;custom-event-data&gt;</t>
                    </list>
                </t>

                <t>where &lt;event-id&gt; uniquely identifies the event that
                has occurred and &lt;custom-event-data&gt; is event
                specific.</t>

                <t>Several rules must be followed by the server when
                generating events:</t>

                <t>
                    <list style="numbers">
                        <t>Events MUST NOT be sent to any client who has not
                        issued an appropriate SUBSCRIBE command.</t>
                        <t>Events MUST only be sent using the same
                        connection that was used to subscribe to them.</t>
                        <t>When response is being sent to the client, event
                        MUST be inserted in the stream before or after the
                        response, but NOT in the middle. Same is true about
                        the response. It should never be inserted in the
                        middle of the event message as well as any other
                        response.</t>
                    </list>
                </t>

                <t>If the client is not interested in a particular event
                anymore it MAY issue UNSUBSCRIBE command using the following
                syntax:</t>

                <t>
                    <list>
                        <t>UNSUBSCRIBE &lt;event-id&gt;</t>
                    </list>
                </t>

                <t>where &lt;event-id&gt; will be replace by the respective
                event that client is no longer interested in receiving. For
                a list of supported events see <xref target="events" />.</t>

                <t>Example: the fill states of disk stream buffers have
                changed on sampler channel 4 and the LinuxSampler instance
                will react by sending the following message to all clients
                who subscribed to this event:</t>

                <t>
                    <list>
                        <t>NOTIFY:CHANNEL_BUFFER_FILL:4 [35]62%,[33]80%,[37]98%</t>
                    </list>
                </t>

                <t>Which means there are currently three active streams on
                sampler channel 4, where the stream with ID "35" is filled
                by 62%, stream with ID 33 is filled by 80% and stream with
                ID 37 is filled by 98%.</t>

                <t>Clients may choose to open more than one connection to
                the server and use some connections to receive notifications
                while using other connections to issue commands to the
                back-end. This is entirely legal and up to the
                implementation. This does not change the protocol in any way
                and no special restrictions exist on the server to allow or
                disallow this or to track what connections belong to what
                front-ends. Server will listen on a single port, accept
                multiple connections and support protocol described in this
                specification in it's entirety on this single port on each
                connection that it accepted.</t>

                <t>Due to the fact that TCP is used for this communication,
                dead peers will be detected automatically by the OS TCP
                stack. While it may take a while to detect dead peers if no
                traffic is being sent from server to client (TCP keep-alive
                timer is set to 2 hours on many OSes) it will not be an
                issue here as when notifications are sent by the server,
                dead client will be detected quickly.</t>

                <t>When connection is closed for any reason server MUST
                forget all subscriptions that were made on this connection.
                If client reconnects it MUST resubscribe to all events that
                it wants to receive.</t>

            </section>
        </section>

        <section title="Description for control commands" anchor="control_commands">
            <t>This chapter will describe the available control commands
            that can be sent on the TCP connection in detail. Some certain
            commands (e.g. <xref target="GET CHANNEL INFO">"GET CHANNEL INFO"</xref>
            or <xref target="GET ENGINE INFO">"GET ENGINE INFO"</xref>) lead to
            multiple-line responses. In this case LinuxSampler signals the
            end of the response by a "." (single dot) line.</t>

            <section title="Ignored lines and comments">
                <t>White lines, that is lines which only contain space and
                tabulator characters, and lines that start with a "#"
                character are ignored, thus it's possible for example to
                group commands and to place comments in a LSCP script
                file.</t>
            </section>

            <section title="Configuring audio drivers">
                <t>Instances of drivers in LinuxSampler are called devices.
                You can use multiple audio devices simultaneously, e.g. to
                output the sound of one sampler channel using the ALSA audio
                output driver, and on another sampler channel you might want
                to use the JACK audio output driver. For particular audio
                output systems it's also possible to create several devices
                of the same audio output driver, e.g. two separate ALSA
                audio output devices for using two different sound cards at
                the same time. This chapter describes all commands to
                configure LinuxSampler's audio output devices and their
                parameters.</t>

                <t>Instead of defining commands and parameters for each
                driver individually, all possible parameters, their meanings
                and possible values have to be obtained at runtime. This
                makes the protocol a bit abstract, but has the advantage,
                that front-ends can be written independently of what drivers
                are currently implemented and what parameters these drivers
                are actually offering. This means front-ends can even handle
                drivers which are implemented somewhere in future without
                modifying the front-end at all.</t>

                <t>Note: examples in this chapter showing particular
                parameters of drivers are not meant as specification of the
                drivers' parameters. Driver implementations in LinuxSampler
                might have complete different parameter names and meanings
                than shown in these examples or might change in future, so
                these examples are only meant for showing how to retrieve
                what parameters drivers are offering, how to retrieve their
                possible values, etc.</t>

                <section title="Getting amount of available audio output drivers" anchor="GET AVAILABLE_AUDIO_OUTPUT_DRIVERS">
                    <t>Use the following command to get the number of
                    audio output drivers currently available for the
                    LinuxSampler instance:</t>
                    <t>
                        <list>
                            <t>GET AVAILABLE_AUDIO_OUTPUT_DRIVERS</t>
                        </list>
                    </t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending the
                            number of audio output drivers.</t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "GET AVAILABLE_AUDIO_OUTPUT_DRIVERS"</t>
                            <t>S: "2"</t>
                        </list>
                    </t>
                </section>

                <section title="Getting all available audio output drivers" anchor="LIST AVAILABLE_AUDIO_OUTPUT_DRIVERS">
                    <t>Use the following command to list all audio output
                    drivers currently available for the LinuxSampler
                    instance:</t>
                    <t>
                        <list>
                            <t>LIST AVAILABLE_AUDIO_OUTPUT_DRIVERS</t>
                        </list>
                    </t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending comma
                            separated character strings, each symbolizing an
                            audio output driver.</t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "LIST AVAILABLE_AUDIO_OUTPUT_DRIVERS"</t>
                            <t>S: "ALSA,JACK"</t>
                        </list>
                    </t>
                </section>

                <section title="Getting information about a specific audio
                output driver" anchor="GET AUDIO_OUTPUT_DRIVER INFO">
                    <t>Use the following command to get detailed information
                    about a specific audio output driver:</t>
                    <t>
                        <list>
                            <t>GET AUDIO_OUTPUT_DRIVER INFO
                             &lt;audio-output-driver&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;audio-output-driver&gt; is the name of the
                    audio output driver, returned by the
                    <xref target="LIST AVAILABLE_AUDIO_OUTPUT_DRIVERS">"LIST AVAILABLE_AUDIO_OUTPUT_DRIVERS"</xref> command.</t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending a
                            &lt;CRLF&gt; separated list. Each answer line
                            begins with the information category name
                            followed by a colon and then a space character
                            &lt;SP&gt; and finally the info character string
                            to that info category. At the moment the
                            following information categories are
                            defined:</t>

                            <t>
                              <list>
                                  <t>DESCRIPTION -
                                    <list>
                                      <t> character string describing the
                                      audio output driver</t>
                                    </list>
                                  </t>

                                  <t>VERSION -
                                    <list>
                                      <t>character string reflecting the
                                      driver's version</t>
                                    </list>
                                  </t>

                                  <t>PARAMETERS -
                                    <list>
                                      <t>comma separated list of all
                                      parameters available for the given
                                      audio output driver, at least
                                      parameters 'channels', 'samplerate'
                                      and 'active' are offered by all audio
                                      output drivers</t>
                                    </list>
                                  </t>
                              </list>
                            </t>

                            <t>The mentioned fields above don't have to be
                            in particular order.</t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                      <list>
                          <t>C: "GET AUDIO_OUTPUT_DRIVER INFO ALSA"</t>
                          <t>S: "DESCRIPTION: Advanced Linux Sound
                          Architecture"</t>
                          <t>&nbsp;&nbsp;&nbsp;"VERSION: 1.0"</t>
                          <t>&nbsp;&nbsp;&nbsp;"PARAMETERS:
                          DRIVER,CHANNELS,SAMPLERATE,ACTIVE,FRAGMENTS,
                          FRAGMENTSIZE,CARD"</t>
                          <t>&nbsp;&nbsp;&nbsp;"."</t>
                      </list>
                    </t>
                </section>

                <section title="Getting information about specific audio
                output driver parameter" anchor="GET AUDIO_OUTPUT_DRIVER_PARAMETER INFO">
                    <t>Use the following command to get detailed information
                    about a  specific audio output driver parameter:</t>
                    <t>
                        <list>
                            <t>GET AUDIO_OUTPUT_DRIVER_PARAMETER INFO &lt;audio&gt; &lt;prm&gt; [&lt;deplist&gt;]</t>
                        </list>
                    </t>
                    <t>Where &lt;audio&gt; is the name of the audio output
                    driver as returned by the <xref target="LIST AVAILABLE_AUDIO_OUTPUT_DRIVERS">
                    "LIST AVAILABLE_AUDIO_OUTPUT_DRIVERS"</xref> command,
                    &lt;prm&gt; a specific parameter name for which information should be
                    obtained (as returned by the
                    <xref target="GET AUDIO_OUTPUT_DRIVER INFO">"GET AUDIO_OUTPUT_DRIVER INFO"</xref> command) and
                    &lt;deplist&gt; is an optional list of parameters on which the sought
                    parameter &lt;prm&gt; depends on, &lt;deplist&gt; is a list of key-value
                    pairs in form of "key1=val1 key2=val2 ...", where character string values
                    are encapsulated into apostrophes ('). Arguments given with &lt;deplist&gt;
                    which are not dependency parameters of &lt;prm&gt; will be ignored, means
                    the front-end application can simply put all parameters into &lt;deplist&gt;
                    with the values already selected by the user.</t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending a
                            &lt;CRLF&gt; separated list.
                            Each answer line begins with the information category name
                            followed by a colon and then a space character &lt;SP&gt; and
                            finally
                            the info character string to that info category. There are
                            information which is always returned, independently of the
                            given driver parameter and there are optional information
                            which is only shown dependently to given driver parameter. At
                            the moment the following information categories are defined:</t>
                        </list>
                    </t>

                    <t>
                        <list>
                            <t>TYPE -
                              <list>
                                <t>either "BOOL" for boolean value(s) or
                                "INT" for integer
                                value(s) or "FLOAT" for dotted number(s) or "STRING" for
                                character string(s)
                                (always returned, no matter which driver parameter)</t>
                              </list>
                            </t>

                            <t>DESCRIPTION -
                              <list>
                                <t>arbitrary text describing the purpose of the parameter
                                (always returned, no matter which driver parameter)</t>
                              </list>
                            </t>

                            <t>MANDATORY -
                              <list>
                                <t>either true or false, defines if this parameter must be
                                given when the device is to be created with the
                                <xref target="CREATE AUDIO_OUTPUT_DEVICE">'CREATE AUDIO_OUTPUT_DEVICE'</xref>
                                command (always returned, no matter which driver parameter)</t>
                              </list>
                            </t>

                            <t>FIX -
                              <list>
                                <t>either true or false, if false then this parameter can
                                be changed at any time, once the device is created by
                                the <xref target="CREATE AUDIO_OUTPUT_DEVICE">'CREATE AUDIO_OUTPUT_DEVICE'</xref>
                                command (always returned, no matter which driver parameter)</t>
                              </list>
                            </t>

                            <t>MULTIPLICITY -
                              <list>
                                <t>either true or false, defines if this parameter allows
                                only one value or a list of values, where true means
                                multiple values and false only a single value allowed
                                (always returned, no matter which driver parameter)</t>
                              </list>
                            </t>

                            <t>DEPENDS -
                              <list>
                                <t>comma separated list of parameters this parameter depends
                                on, means the values for fields 'DEFAULT', 'RANGE_MIN',
                                'RANGE_MAX' and 'POSSIBILITIES' might depend on these
                                listed parameters, for example assuming that an audio
                                driver (like the ALSA driver) offers parameters 'card'
                                and 'samplerate' then parameter 'samplerate' would
                                depend on 'card' because the possible values for
                                'samplerate' depends on the sound card which can be
                                chosen by the 'card' parameter
                                (optionally returned, dependent to driver parameter)</t>
                              </list>
                            </t>

                            <t>DEFAULT -
                              <list>
                                <t>reflects the default value for this parameter which is
                                used when the device is created and not explicitly
                                given with the <xref target="CREATE AUDIO_OUTPUT_DEVICE">
                                'CREATE AUDIO_OUTPUT_DEVICE'</xref> command,
                                in case of MULTIPLCITY=true, this is a comma separated
                                list, that's why character strings are encapsulated into
                                apostrophes (')
                                (optionally returned, dependent to driver parameter)</t>
                              </list>
                            </t>

                            <t>RANGE_MIN -
                              <list>
                                <t>defines lower limit of the allowed value range for this
                                parameter, can be an integer value as well as a dotted
                                number, this parameter is often used in conjunction
                                with RANGE_MAX, but may also appear without
                                (optionally returned, dependent to driver parameter)</t>
                              </list>
                            </t>

                            <t>RANGE_MAX -
                              <list>
                                <t>defines upper limit of the allowed value range for this
                                parameter, can be an integer value as well as a dotted
                                number, this parameter is often used in conjunction with
                                RANGE_MIN, but may also appear without
                                (optionally returned, dependent to driver parameter)</t>
                              </list>
                            </t>

                            <t>POSSIBILITIES -
                              <list>
                                <t>comma separated list of possible values for this
                                parameter, character strings are encapsulated into
                                apostrophes
                                (optionally returned, dependent to driver parameter)</t>
                              </list>
                            </t>
                        </list>
                    </t>

                    <t>The mentioned fields above don't have to be in particular order.</t>

                    <t>Examples:</t>
                    <t>
                        <list>
                            <t>C: "GET AUDIO_OUTPUT_DRIVER_PARAMETER INFO ALSA CARD"</t>
                            <t>S: "DESCRIPTION: sound card to be used"</t>
                            <t>&nbsp;&nbsp;&nbsp;"TYPE: STRING"</t>
                            <t>&nbsp;&nbsp;&nbsp;"MANDATORY: false"</t>
                            <t>&nbsp;&nbsp;&nbsp;"FIX: true"</t>
                            <t>&nbsp;&nbsp;&nbsp;"MULTIPLICITY: false"</t>
                            <t>&nbsp;&nbsp;&nbsp;"DEFAULT: '0,0'"</t>
                            <t>&nbsp;&nbsp;&nbsp;"POSSIBILITIES: '0,0','1,0','2,0'"</t>
                            <t>&nbsp;&nbsp;&nbsp;"."</t>
                        </list>
                    </t>
                    <t>
                        <list>
                            <t>C: "GET AUDIO_OUTPUT_DRIVER_PARAMETER INFO ALSA SAMPLERATE"</t>
                            <t>S: "DESCRIPTION: output sample rate in Hz"</t>
                            <t>&nbsp;&nbsp;&nbsp;"TYPE: INT"</t>
                            <t>&nbsp;&nbsp;&nbsp;"MANDATORY: false"</t>
                            <t>&nbsp;&nbsp;&nbsp;"FIX: false"</t>
                            <t>&nbsp;&nbsp;&nbsp;"MULTIPLICITY: false"</t>
                            <t>&nbsp;&nbsp;&nbsp;"DEPENDS: card"</t>
                            <t>&nbsp;&nbsp;&nbsp;"DEFAULT: 44100"</t>
                            <t>&nbsp;&nbsp;&nbsp;"."</t>
                        </list>
                    </t>
                    <t>
                        <list>
                            <t>C: "GET AUDIO_OUTPUT_DRIVER_PARAMETER INFO ALSA SAMPLERATE CARD='0,0'"</t>
                            <t>S: "DESCRIPTION: output sample rate in Hz"</t>
                            <t>&nbsp;&nbsp;&nbsp;"TYPE: INT"</t>
                            <t>&nbsp;&nbsp;&nbsp;"MANDATORY: false"</t>
                            <t>&nbsp;&nbsp;&nbsp;"FIX: false"</t>
                            <t>&nbsp;&nbsp;&nbsp;"MULTIPLICITY: false"</t>
                            <t>&nbsp;&nbsp;&nbsp;"DEPENDS: card"</t>
                            <t>&nbsp;&nbsp;&nbsp;"DEFAULT: 44100"</t>
                            <t>&nbsp;&nbsp;&nbsp;"RANGE_MIN: 22050"</t>
                            <t>&nbsp;&nbsp;&nbsp;"RANGE_MAX: 96000"</t>
                            <t>&nbsp;&nbsp;&nbsp;"."</t>
                        </list>
                    </t>
                </section>

                <section title="Creating an audio output device" anchor="CREATE AUDIO_OUTPUT_DEVICE">
                    <t>Use the following command to create a new audio output device for  the desired audio output system:</t>

                    <t>
                        <list>
                            <t>CREATE AUDIO_OUTPUT_DEVICE &lt;audio-output-driver&gt; [&lt;param-list&gt;]</t>
                        </list>
                    </t>

                    <t>Where &lt;audio-output-driver&gt; should be replaced by the desired audio
                    output system as returned by the
                    <xref target="LIST AVAILABLE_AUDIO_OUTPUT_DRIVERS">"LIST AVAILABLE_AUDIO_OUTPUT_DRIVERS"</xref>
                    command and &lt;param-list&gt; by an optional list of driver
                    specific parameters in form of "key1=val1 key2=val2 ...", where
                    character string values should be encapsulated into apostrophes (').
                    Note that there might be drivers which require parameter(s) to be
                    given with this command. Use the previously described commands in
                    this chapter to get this information.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK[&lt;device-id&gt;]" -
                                <list>
                                    <t>in case the device was successfully created, where
                                    &lt;device-id&gt; is the numerical ID of the new device</t>
                                </list>
                            </t>
                            <t>"WRN[&lt;device-id&gt;]:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>in case the device was created successfully, where
                                    &lt;device-id&gt; is the numerical ID of the new device, but there
                                    are noteworthy issue(s) related (e.g. sound card doesn't
                                    support given hardware parameters and the driver is using
                                    fall-back values), providing an appropriate warning code and
                                    warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Examples:</t>
                    <t>
                        <list>
                            <t>C: "CREATE AUDIO_OUTPUT_DEVICE ALSA"</t>
                            <t>S: "OK[0]"</t>
                        </list>
                    </t>
                    <t>
                        <list>
                            <t>C: "CREATE AUDIO_OUTPUT_DEVICE ALSA CARD='2,0' SAMPLERATE=96000"</t>
                            <t>S: "OK[1]"</t>
                        </list>
                    </t>
                </section>

                <section title="Destroying an audio output device" anchor="DESTROY AUDIO_OUTPUT_DEVICE">
                    <t>Use the following command to destroy a created output device:</t>
                    <t>
                        <list>
                            <t>DESTROY AUDIO_OUTPUT_DEVICE &lt;device-id&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;device-id&gt; should be replaced by the numerical ID of the
                    audio output device as given by the
                    <xref target="CREATE AUDIO_OUTPUT_DEVICE">"CREATE AUDIO_OUTPUT_DEVICE"</xref>
                    or <xref target="LIST AUDIO_OUTPUT_DEVICES">"LIST AUDIO_OUTPUT_DEVICES"</xref>
                    command.</t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>in case the device was successfully destroyed</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>in case the device was destroyed successfully, but there are
                                    noteworthy issue(s) related (e.g. an audio over ethernet
                                    driver was unloaded but the other host might not be
                                    informed about this situation), providing an appropriate
                                    warning code and warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and
                                    error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "DESTROY AUDIO_OUTPUT_DEVICE 0"</t>
                            <t>S: "OK"</t>
                        </list>
                    </t>
                </section>

                <section title="Getting all created audio output device count" anchor="GET AUDIO_OUTPUT_DEVICES">
                    <t>Use the following command to count all created audio output devices:</t>
                    <t>
                        <list>
                            <t>GET AUDIO_OUTPUT_DEVICES</t>
                        </list>
                    </t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending the current number of all
                            audio output devices.</t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "GET AUDIO_OUTPUT_DEVICES"</t>
                            <t>S: "4"</t>
                        </list>
                    </t>
                </section>

                <section title="Getting all created audio output device list" anchor="LIST AUDIO_OUTPUT_DEVICES">
                    <t>Use the following command to list all created audio output devices:</t>
                    <t>
                        <list>
                            <t>LIST AUDIO_OUTPUT_DEVICES</t>
                        </list>
                    </t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending a comma separated list with
                            the numerical IDs of all audio output devices.</t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "LIST AUDIO_OUTPUT_DEVICES"</t>
                            <t>S: "0,1,4,5"</t>
                        </list>
                    </t>
                </section>

                <section title="Getting current settings of an audio output device" anchor="GET AUDIO_OUTPUT_DEVICE INFO">
                    <t>Use the following command to get current settings of a specific, created audio output device:</t>
                    <t>
                        <list>
                            <t>GET AUDIO_OUTPUT_DEVICE INFO &lt;device-id&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;device-id&gt; should be replaced by numerical ID
                    of the audio output device as e.g. returned by the
                    <xref target="LIST AUDIO_OUTPUT_DEVICES">"LIST AUDIO_OUTPUT_DEVICES"</xref> command.</t>
                    <t>Possible Answers:</t>
                    <t>LinuxSampler will answer by sending a &lt;CRLF&gt; separated list.
                    Each answer line begins with the information category name
                    followed by a colon and then a space character &lt;SP&gt; and finally
                    the info character string to that info category. As some
                    parameters might allow multiple values, character strings are
                    encapsulated into apostrophes ('). At the moment the following
                    information categories are defined (independently of device):</t>
                    <t>
                        <list>
                            <t>DRIVER -
                                <list>
                                    <t>identifier of the used audio output driver, as also
                                    returned by the
                                    <xref target="LIST AVAILABLE_AUDIO_OUTPUT_DRIVERS">
                                    "LIST AVAILABLE_AUDIO_OUTPUT_DRIVERS"</xref>
                                    command</t>
                                </list>
                            </t>
                            <t>CHANNELS -
                                <list>
                                    <t>amount of audio output channels this device currently
                                    offers</t>
                                </list>
                            </t>
                            <t>SAMPLERATE -
                                <list>
                                    <t>playback sample rate the device uses</t>
                                </list>
                            </t>
                            <t>ACTIVE -
                                <list>
                                    <t>either true or false, if false then the audio device is
                                    inactive and doesn't output any sound, nor do the
                                    sampler channels connected to this audio device render
                                    any audio</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>The mentioned fields above don't have to be in particular
                    order. The fields above are only those fields which are
                    returned by all audio output devices. Every audio output driver
                    might have its own, additional driver specific parameters (see
                    <xref target="GET AUDIO_OUTPUT_DRIVER INFO" />)
                    which are also returned by this command.</t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "GET AUDIO_OUTPUT_DEVICE INFO 0"</t>
                            <t>S: "DRIVER: ALSA"</t>
                            <t>&nbsp;&nbsp;&nbsp;"CHANNELS: 2"</t>
                            <t>&nbsp;&nbsp;&nbsp;"SAMPLERATE: 44100"</t>
                            <t>&nbsp;&nbsp;&nbsp;"ACTIVE: true"</t>
                            <t>&nbsp;&nbsp;&nbsp;"FRAGMENTS: 2"</t>
                            <t>&nbsp;&nbsp;&nbsp;"FRAGMENTSIZE: 128"</t>
                            <t>&nbsp;&nbsp;&nbsp;"CARD: '0,0'"</t>
                            <t>&nbsp;&nbsp;&nbsp;"."</t>
                        </list>
                    </t>
                </section>


                <section title="Changing settings of audio output devices" anchor="SET AUDIO_OUTPUT_DEVICE_PARAMETER">
                    <t>Use the following command to alter a specific setting of a created audio output device:</t>
                    <t>
                        <list>
                            <t>SET AUDIO_OUTPUT_DEVICE_PARAMETER &lt;device-id&gt; &lt;key&gt;=&lt;value&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;device-id&gt; should be replaced by the numerical ID of the
                    audio output device as given by the
                    <xref target="CREATE AUDIO_OUTPUT_DEVICE">"CREATE AUDIO_OUTPUT_DEVICE"</xref>
                    or <xref target="LIST AUDIO_OUTPUT_DEVICES">"LIST AUDIO_OUTPUT_DEVICES"</xref>
                    command, &lt;key&gt; by the name of the parameter to change
                    and &lt;value&gt; by the new value for this parameter.</t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>in case setting was successfully changed</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>in case setting was changed successfully, but there are
                                    noteworthy issue(s) related, providing an appropriate
                                    warning code and warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and
                                    error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "SET AUDIO_OUTPUT_DEVICE_PARAMETER 0 FRAGMENTSIZE=128"</t>
                            <t>S: "OK"</t>
                        </list>
                    </t>
                </section>

                <section title="Getting information about an audio channel" anchor="GET AUDIO_OUTPUT_CHANNEL INFO">
                    <t>Use the following command to get information about an audio channel:</t>
                    <t>
                        <list>
                            <t>GET AUDIO_OUTPUT_CHANNEL INFO &lt;device-id&gt; &lt;audio-chan&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;device-id&gt; is the numerical ID of the audio output device as given by the
                    <xref target="CREATE AUDIO_OUTPUT_DEVICE">"CREATE AUDIO_OUTPUT_DEVICE"</xref>
                    or <xref target="LIST AUDIO_OUTPUT_DEVICES">"LIST AUDIO_OUTPUT_DEVICES"</xref>
                    command and &lt;audio-chan&gt; the audio channel number.</t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending a &lt;CRLF&gt; separated list.
                            Each answer line begins with the information category name
                            followed by a colon and then a space character &lt;SP&gt; and finally
                            the info character string to that info category. At the moment
                            the following information categories are defined:</t>

                            <t>
                                <list>
                                    <t>NAME -
                                        <list>
                                            <t>arbitrary character string naming the channel, which
                                            doesn't have to be unique (always returned by all audio channels)</t>
                                        </list>
                                    </t>
                                    <t>IS_MIX_CHANNEL -
                                        <list>
                                            <t>either true or false, a mix-channel is not a real,
                                            independent audio channel, but a virtual channel which
                                            is mixed to another real channel, this mechanism is
                                            needed for sampler engines which need more audio
                                            channels than the used audio system might be able to offer
                                            (always returned by all audio channels)</t>
                                        </list>
                                    </t>
                                    <t>MIX_CHANNEL_DESTINATION -
                                        <list>
                                            <t>numerical ID (positive integer including 0)
                                            which reflects the real audio channel (of the same audio
                                            output device) this mix channel refers to, means where
                                            the audio signal actually will be routed / added to
                                            (only returned in case the audio channel is mix channel)</t>
                                        </list>
                                    </t>
                                </list>
                            </t>
                        </list>
                    </t>

                    <t>The mentioned fields above don't have to be in particular
                    order. The fields above are only those fields which are
                    generally returned for the described cases by all audio
                    channels regardless of the audio driver. Every audio channel
                    might have its own, additional driver and channel specific
                    parameters.</t>

                    <t>Examples:</t>

                    <t>
                        <list>
                            <t>C: "GET AUDIO_OUTPUT_CHANNEL INFO 0 0"</t>
                            <t>S: "NAME: studio monitor left"</t>
                            <t>&nbsp;&nbsp;&nbsp;"IS_MIX_CHANNEL: false"</t>
                            <t>&nbsp;&nbsp;&nbsp;"."</t>
                        </list>
                    </t>

                    <t>
                        <list>
                            <t>C: "GET AUDIO_OUTPUT_CHANNEL INFO 0 1"</t>
                            <t>S: "NAME: studio monitor right"</t>
                            <t>&nbsp;&nbsp;&nbsp;"IS_MIX_CHANNEL: false"</t>
                            <t>&nbsp;&nbsp;&nbsp;"."</t>
                         </list>
                    </t>

                    <t>
                        <list>
                            <t>C: "GET AUDIO_OUTPUT_CHANNEL INFO 0 2"</t>
                            <t>S: "NAME: studio monitor left"</t>
                            <t>&nbsp;&nbsp;&nbsp;"IS_MIX_CHANNEL: true"</t>
                            <t>&nbsp;&nbsp;&nbsp;"MIX_CHANNEL_DESTINATION: 1"</t>
                            <t>&nbsp;&nbsp;&nbsp;"."</t>
                        </list>
                    </t>

                    <t>
                        <list>
                            <t>C: "GET AUDIO_OUTPUT_CHANNEL INFO 1 0"</t>
                            <t>S: "NAME: 'ardour (left)'"</t>
                            <t>&nbsp;&nbsp;&nbsp;"IS_MIX_CHANNEL: false"</t>
                            <t>&nbsp;&nbsp;&nbsp;"JACK_BINDINGS: 'ardour:0'"</t>
                            <t>&nbsp;&nbsp;&nbsp;"."</t>
                        </list>
                    </t>
                </section>

                <section title="Getting information about specific audio channel parameter" anchor="GET AUDIO_OUTPUT_CHANNEL_PARAMETER INFO">
                    <t>Use the following command to get detailed information about specific audio channel parameter:</t>

                    <t>
                        <list>
                            <t>GET AUDIO_OUTPUT_CHANNEL_PARAMETER INFO &lt;dev-id&gt; &lt;chan&gt; &lt;param&gt;</t>
                        </list>
                    </t>

                    <t>Where &lt;dev-id&gt; is the numerical ID of the audio output device as returned by the
                    <xref target="CREATE AUDIO_OUTPUT_DEVICE">"CREATE AUDIO_OUTPUT_DEVICE"</xref>
                    or <xref target="LIST AUDIO_OUTPUT_DEVICES">"LIST AUDIO_OUTPUT_DEVICES"</xref>
                    command, &lt;chan&gt; the audio channel number
                    and &lt;param&gt; a specific channel parameter name for which information should
                    be obtained (as returned by the <xref target="GET AUDIO_OUTPUT_CHANNEL INFO">
                    "GET AUDIO_OUTPUT_CHANNEL INFO"</xref> command).</t>
                    <t>Possible Answers:</t>

                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending a &lt;CRLF&gt; separated list.
                            Each answer line begins with the information category name
                            followed by a colon and then a space character &lt;SP&gt; and finally
                            the info character string to that info category. There are
                            information which is always returned, independently of the
                            given channel parameter and there is optional information
                            which is only shown dependently to the given audio channel. At
                            the moment the following information categories are defined:</t>
                            <t>
                                <list>
                                    <t>TYPE -
                                        <list>
                                            <t>either "BOOL" for boolean value(s) or "INT" for integer
                                            value(s) or "FLOAT" for dotted number(s) or "STRING" for
                                            character string(s)
                                            (always returned)</t>
                                        </list>
                                    </t>
                                    <t>DESCRIPTION -
                                        <list>
                                            <t>arbitrary text describing the purpose of the parameter (always returned)</t>
                                        </list>
                                    </t>
                                    <t>FIX -
                                        <list>
                                            <t>either true or false, if true then this parameter is
                                            read only, thus cannot be altered
                                            (always returned)</t>
                                        </list>
                                    </t>
                                    <t>MULTIPLICITY -
                                        <list>
                                            <t>either true or false, defines if this parameter allows
                                            only one value or a list of values, where true means
                                            multiple values and false only a single value allowed
                                            (always returned)</t>
                                        </list>
                                    </t>
                                    <t>RANGE_MIN -
                                        <list>
                                            <t>defines lower limit of the allowed value range for this
                                            parameter, can be an integer value as well as a dotted
                                            number, usually used in conjunction with 'RANGE_MAX',
                                            but may also appear without
                                            (optionally returned, dependent to driver and channel
                                            parameter)</t>
                                        </list>
                                    </t>
                                    <t>RANGE_MAX -
                                        <list>
                                            <t>defines upper limit of the allowed value range for this
                                            parameter, can be an integer value as well as a dotted
                                            number, usually used in conjunction with 'RANGE_MIN',
                                            but may also appear without
                                            (optionally returned, dependent to driver and channel
                                            parameter)</t>
                                        </list>
                                    </t>
                                    <t>POSSIBILITIES -
                                        <list>
                                            <t>comma separated list of possible values for this
                                            parameter, character strings are encapsulated into
                                            apostrophes
                                            (optionally returned, dependent to driver and channel
                                            parameter)</t>
                                        </list>
                                    </t>
                                </list>
                            </t>
                            <t>The mentioned fields above don't have to be in particular order.</t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "GET AUDIO_OUTPUT_CHANNEL_PARAMETER INFO 1 0 JACK_BINDINGS"</t>
                            <t>S: "DESCRIPTION: bindings to other JACK clients"</t>
                            <t>&nbsp;&nbsp;&nbsp;"TYPE: STRING"</t>
                            <t>&nbsp;&nbsp;&nbsp;"FIX: false"</t>
                            <t>&nbsp;&nbsp;&nbsp;"MULTIPLICITY: true"</t>
                            <t>&nbsp;&nbsp;&nbsp;"POSSIBILITIES: 'PCM:0','PCM:1','ardour:0','ardour:1'"</t>
                            <t>&nbsp;&nbsp;&nbsp;"."</t>
                        </list>
                    </t>
                </section>

                <section title="Changing settings of audio output channels" anchor="SET AUDIO_OUTPUT_CHANNEL_PARAMETER">
                    <t>Use the following command to alter a specific setting of an audio output channel:</t>
                    <t>
                        <list>
                            <t>SET AUDIO_OUTPUT_CHANNEL_PARAMETER &lt;dev-id&gt; &lt;chn&gt; &lt;key&gt;=&lt;value&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;dev-id&gt; should be replaced by the numerical ID of the audio output device as returned by the
                    <xref target="CREATE AUDIO_OUTPUT_DEVICE">"CREATE AUDIO_OUTPUT_DEVICE"</xref>
                    or <xref target="LIST AUDIO_OUTPUT_DEVICES">"LIST AUDIO_OUTPUT_DEVICES"</xref>
                    command, &lt;chn&gt; by the audio channel number, &lt;key&gt; by the name of the
                    parameter to change and &lt;value&gt; by the new value for this parameter.</t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                   <t>in case setting was successfully changed</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                   <t>in case setting was changed successfully, but there are
                                   noteworthy issue(s) related, providing an appropriate
                                   warning code and warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                   <t>in case it failed, providing an appropriate error code and
                                   error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "SET AUDIO_OUTPUT_CHANNEL PARAMETER 0 0 JACK_BINDINGS='PCM:0'"</t>
                            <t>S: "OK"</t>
                        </list>
                    </t>
                    <t>
                        <list>
                            <t>C: "SET AUDIO_OUTPUT_CHANNEL PARAMETER 0 0 NAME='monitor left'"</t>
                            <t>S: "OK"</t>
                        </list>
                    </t>
                </section>
            </section>

            <section title="Configuring MIDI input drivers">
                <t>Instances of drivers in LinuxSampler are called devices. You can use
                multiple MIDI devices simultaneously, e.g. to use MIDI over ethernet as
                MIDI input on one sampler channel and ALSA as MIDI input on another sampler
                channel. For particular MIDI input systems it's also possible to create
                several devices of the same MIDI input type. This chapter describes all
                commands to configure LinuxSampler's MIDI input devices and their parameters.</t>

                <t>Instead of defining commands and parameters for each driver individually,
                all possible parameters, their meanings and possible values have to be obtained
                at runtime. This makes the protocol a bit abstract, but has the advantage, that
                front-ends can be written independently of what drivers are currently implemented
                and what parameters these drivers are actually offering. This means front-ends can
                even handle drivers which are implemented somewhere in future without modifying
                the front-end at all.</t>

                <t>Commands for configuring MIDI input devices are pretty much the same as the
                commands for configuring audio output drivers, already described in the last
                chapter.</t>

                <t>Note: examples in this chapter showing particular parameters of drivers are
                not meant as specification of the drivers' parameters. Driver implementations in
                LinuxSampler might have complete different parameter names and meanings than shown
                in these examples or might change in future, so these examples are only meant for
                showing how to retrieve what parameters drivers are offering, how to retrieve their
                possible values, etc.</t>

                <section title="Getting amount of available MIDI input drivers" anchor="GET AVAILABLE_MIDI_INPUT_DRIVERS">
                    <t>Use the following command to get the number of
                    MIDI input drivers currently available for the
                    LinuxSampler instance:</t>
                    <t>
                        <list>
                            <t>GET AVAILABLE_MIDI_INPUT_DRIVERS</t>
                        </list>
                    </t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending the
                            number of available MIDI input drivers.</t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "GET AVAILABLE_MIDI_INPUT_DRIVERS"</t>
                            <t>S: "2"</t>
                        </list>
                    </t>
                </section>

                <section title="Getting all available MIDI input drivers" anchor="LIST AVAILABLE_MIDI_INPUT_DRIVERS">
                    <t>Use the following command to list all MIDI input drivers currently available
                    for the LinuxSampler instance:</t>
                    <t>
                        <list>
                            <t>LIST AVAILABLE_MIDI_INPUT_DRIVERS</t>
                        </list>
                    </t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending comma separated character
                            strings, each symbolizing a MIDI input driver.</t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "LIST AVAILABLE_MIDI_INPUT_DRIVERS"</t>
                            <t>S: "ALSA,JACK"</t>
                        </list>
                    </t>
                </section>

                <section title="Getting information about a specific MIDI input driver" anchor="GET MIDI_INPUT_DRIVER INFO">
                    <t>Use the following command to get detailed information about a specific MIDI input driver:</t>
                    <t>
                        <list>
                            <t>GET MIDI_INPUT_DRIVER INFO &lt;midi-input-driver&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;midi-input-driver&gt; is the name of the MIDI input driver as returned
                    by the <xref target="LIST AVAILABLE_MIDI_INPUT_DRIVERS">
                    "LIST AVAILABLE_MIDI_INPUT_DRIVERS"</xref> command.</t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending a &lt;CRLF&gt; separated list.
                            Each answer line begins with the information category name
                            followed by a colon and then a space character &lt;SP&gt; and finally
                            the info character string to that info category. At the moment
                            the following information categories are defined:</t>

                            <t>
                                <list>
                                    <t>DESCRIPTION -
                                        <list>
                                            <t>arbitrary description text about the MIDI input driver</t>
                                        </list>
                                    </t>
                                    <t>VERSION -
                                        <list>
                                            <t>arbitrary character string regarding the driver's version</t>
                                        </list>
                                    </t>
                                    <t>PARAMETERS -
                                        <list>
                                            <t>comma separated list of all parameters available for the given MIDI input driver</t>
                                        </list>
                                    </t>
                                </list>
                            </t>

                            <t>The mentioned fields above don't have to be in particular order.</t>
                        </list>
                    </t>

                    <t>Example:</t>

                    <t>
                        <list>
                            <t>C: "GET MIDI_INPUT_DRIVER INFO ALSA"</t>
                            <t>S: "DESCRIPTION: Advanced Linux Sound Architecture"</t>
                            <t>&nbsp;&nbsp;&nbsp;"VERSION: 1.0"</t>
                            <t>&nbsp;&nbsp;&nbsp;"PARAMETERS: DRIVER,ACTIVE"</t>
                            <t>&nbsp;&nbsp;&nbsp;"."</t>
                        </list>
                    </t>
                </section>

                <section title="Getting information about specific MIDI input driver parameter" anchor="GET MIDI_INPUT_DRIVER_PARAMETER INFO">
                    <t>Use the following command to get detailed information about a specific parameter of a specific MIDI input driver:</t>
                    <t>
                        <list>
                            <t>GET MIDI_INPUT_DRIVER_PARAMETER INFO &lt;midit&gt; &lt;param&gt; [&lt;deplist&gt;]</t>
                        </list>
                    </t>

                    <t>Where &lt;midit&gt; is the name of the MIDI input driver as returned
                    by the <xref target="LIST AVAILABLE_MIDI_INPUT_DRIVERS">
                    "LIST AVAILABLE_MIDI_INPUT_DRIVERS"</xref> command, &lt;param&gt; a specific
                    parameter name for which information should be obtained (as returned by the
                    <xref target="GET MIDI_INPUT_DRIVER INFO">
                    "GET MIDI_INPUT_DRIVER INFO"</xref> command) and &lt;deplist&gt; is an optional list
                    of parameters on which the sought parameter &lt;param&gt; depends on,
                    &lt;deplist&gt; is a key-value pair list in form of "key1=val1 key2=val2 ...",
                    where character string values are encapsulated into apostrophes ('). Arguments
                    given with &lt;deplist&gt; which are not dependency parameters of &lt;param&gt;
                    will be ignored, means the front-end application can simply put all parameters
                    in &lt;deplist&gt; with the values selected by the user.</t>

                    <t>Possible Answers:</t>

                    <t>LinuxSampler will answer by sending a &lt;CRLF> separated list.
                    Each answer line begins with the information category name
                    followed by a colon and then a space character &lt;SP> and finally
                    the info character string to that info category. There is
                    information which is always returned, independent of the
                    given driver parameter and there is optional information
                    which is only shown dependent to given driver parameter. At
                    the moment the following information categories are defined:</t>

                    <t>
                        <list>
                            <t>TYPE -
                              <list>
                                <t>either "BOOL" for boolean value(s) or "INT" for integer
                                value(s) or "FLOAT" for dotted number(s) or "STRING" for
                                character string(s)
                                (always returned, no matter which driver parameter)</t>
                              </list>
                            </t>

                            <t>DESCRIPTION -
                              <list>
                                <t>arbitrary text describing the purpose of the parameter
                                (always returned, no matter which driver parameter)</t>
                              </list>
                            </t>

                            <t>MANDATORY -
                              <list>
                                <t>either true or false, defines if this parameter must be
                                given when the device is to be created with the
                                <xref target="CREATE MIDI_INPUT_DEVICE">
                                'CREATE MIDI_INPUT_DEVICE'</xref> command
                                (always returned, no matter which driver parameter)</t>
                              </list>
                            </t>

                            <t>FIX -
                              <list>
                                <t>either true or false, if false then this parameter can
                                be changed at any time, once the device is created by
                                the <xref target="CREATE MIDI_INPUT_DEVICE">
                                'CREATE MIDI_INPUT_DEVICE'</xref> command
                                (always returned, no matter which driver parameter)</t>
                              </list>
                            </t>

                            <t>MULTIPLICITY -
                              <list>
                                <t>either true or false, defines if this parameter allows
                                only one value or a list of values, where true means
                                multiple values and false only a single value allowed
                                (always returned, no matter which driver parameter)</t>
                              </list>
                            </t>

                            <t>DEPENDS -
                              <list>
                                <t>comma separated list of parameters this parameter depends
                                on, means the values for fields 'DEFAULT', 'RANGE_MIN',
                                'RANGE_MAX' and 'POSSIBILITIES' might depend on these
                                listed parameters, for example assuming that an audio
                                driver (like the ALSA driver) offers parameters 'card'
                                and 'samplerate' then parameter 'samplerate' would
                                depend on 'card' because the possible values for
                                'samplerate' depends on the sound card which can be
                                chosen by the 'card' parameter
                                (optionally returned, dependent to driver parameter)</t>
                              </list>
                            </t>

                            <t>DEFAULT -
                              <list>
                                <t>reflects the default value for this parameter which is
                                used when the device is created and not explicitly
                                given with the <xref target="CREATE MIDI_INPUT_DEVICE">
                                'CREATE MIDI_INPUT_DEVICE'</xref> command,
                                in case of MULTIPLCITY=true, this is a comma separated
                                list, that's why character strings are encapsulated into
                                apostrophes (')
                                (optionally returned, dependent to driver parameter)</t>
                              </list>
                            </t>

                            <t>RANGE_MIN -
                              <list>
                                <t>defines lower limit of the allowed value range for this
                                parameter, can be an integer value as well as a dotted
                                number, this parameter is often used in conjunction
                                with RANGE_MAX, but may also appear without
                                (optionally returned, dependent to driver parameter)</t>
                              </list>
                            </t>

                            <t>RANGE_MAX -
                              <list>
                                <t>defines upper limit of the allowed value range for this
                                parameter, can be an integer value as well as a dotted
                                number, this parameter is often used in conjunction with
                                RANGE_MIN, but may also appear without
                                (optionally returned, dependent to driver parameter)</t>
                              </list>
                            </t>

                            <t>POSSIBILITIES -
                              <list>
                                <t>comma separated list of possible values for this
                                parameter, character strings are encapsulated into
                                apostrophes
                                (optionally returned, dependent to driver parameter)</t>
                              </list>
                            </t>
                        </list>
                    </t>

                    <t>The mentioned fields above don't have to be in particular order.</t>

                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "GET MIDI_INPUT_DRIVER_PARAMETER INFO ALSA ACTIVE"</t>
                            <t>S: "DESCRIPTION: Whether device is enabled"</t>
                            <t>&nbsp;&nbsp;&nbsp;"TYPE: BOOL"</t>
                            <t>&nbsp;&nbsp;&nbsp;"MANDATORY: false"</t>
                            <t>&nbsp;&nbsp;&nbsp;"FIX: false"</t>
                            <t>&nbsp;&nbsp;&nbsp;"MULTIPLICITY: false"</t>
                            <t>&nbsp;&nbsp;&nbsp;"DEFAULT: true"</t>
                            <t>&nbsp;&nbsp;&nbsp;"."</t>
                        </list>
                    </t>
                </section>

                <section title="Creating a MIDI input device" anchor="CREATE MIDI_INPUT_DEVICE">
                    <t>Use the following command to create a new MIDI input device for  the desired MIDI input system:</t>
                    <t>
                        <list>
                            <t>CREATE MIDI_INPUT_DEVICE &lt;midi-input-driver&gt; [&lt;param-list&gt;]</t>
                        </list>
                    </t>

                    <t>Where &lt;midi-input-driver&gt; should be replaced by the desired MIDI input system as returned
                    by the <xref target="LIST AVAILABLE_MIDI_INPUT_DRIVERS">
                    "LIST AVAILABLE_MIDI_INPUT_DRIVERS"</xref> command and &lt;param-list&gt; by an
                    optional list of driver specific parameters in form of "key1=val1 key2=val2 ...", where
                    character string values should be encapsulated into apostrophes (').
                    Note that there might be drivers which require parameter(s) to be
                    given with this command. Use the previously described commands in
                    this chapter to get that information.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK[&lt;device-id&gt;]" -
                                <list>
                                    <t>in case the device was successfully created, where
                                    &lt;device-id&gt; is the numerical ID of the new device</t>
                                </list>
                            </t>
                            <t>"WRN[&lt;device-id&gt;]:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>in case the driver was loaded successfully, where
                                    &lt;device-id&gt; is the numerical ID of the new device, but
                                    there are noteworthy issue(s) related, providing an
                                    appropriate warning code and warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "CREATE MIDI_INPUT_DEVICE ALSA"</t>
                            <t>S: "OK[0]"</t>
                        </list>
                    </t>
                </section>

                <section title="Destroying a MIDI input device" anchor="DESTROY MIDI_INPUT_DEVICE">
                    <t>Use the following command to destroy a created MIDI input device:</t>
                    <t>
                        <list>
                            <t>DESTROY MIDI_INPUT_DEVICE &lt;device-id&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;device-id&gt; should be replaced by the device's numerical ID as returned by the
                    <xref target="CREATE MIDI_INPUT_DEVICE">"CREATE MIDI_INPUT_DEVICE"</xref>
                    or <xref target="LIST MIDI_INPUT_DEVICES">"LIST MIDI_INPUT_DEVICES"</xref>
                    command.</t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>in case the device was successfully destroyed</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>in case the device was destroyed, but there are noteworthy
                                    issue(s) related, providing an appropriate warning code and
                                    warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "DESTROY MIDI_INPUT_DEVICE 0"</t>
                            <t>S: "OK"</t>
                        </list>
                    </t>
                </section>

                <section title="Getting all created MIDI input device count" anchor="GET MIDI_INPUT_DEVICES">
                    <t>Use the following command to count all created MIDI input devices:</t>
                    <t>
                        <list>
                            <t>GET MIDI_INPUT_DEVICES</t>
                        </list>
                    </t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending the current number of all
                            MIDI input devices.</t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "GET MIDI_INPUT_DEVICES"</t>
                            <t>S: "3"</t>
                        </list>
                    </t>
                </section>


                <section title="Getting all created MIDI input device list" anchor="LIST MIDI_INPUT_DEVICES">
                    <t>Use the following command to list all created MIDI input devices:</t>
                    <t>
                        <list>
                            <t>LIST MIDI_INPUT_DEVICES</t>
                        </list>
                    </t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending a comma separated list
                            with the numerical Ids of all created MIDI input devices.</t>
                        </list>
                    </t>
                    <t>Examples:</t>
                    <t>
                        <list>
                            <t>C: "LIST MIDI_INPUT_DEVICES"</t>
                            <t>S: "0,1,2"</t>
                        </list>
                    </t>
                    <t>
                        <list>
                            <t>C: "LIST MIDI_INPUT_DEVICES"</t>
                            <t>S: "1,3"</t>
                        </list>
                    </t>
                </section>

                <section title="Getting current settings of a MIDI input device" anchor="GET MIDI_INPUT_DEVICE INFO">
                    <t>Use the following command to get current settings of a specific, created MIDI input device:</t>
                    <t>
                        <list>
                            <t>GET MIDI_INPUT_DEVICE INFO &lt;device-id&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;device-id&gt; is the numerical ID of the MIDI input device as returned by the
                    <xref target="CREATE MIDI_INPUT_DEVICE">"CREATE MIDI_INPUT_DEVICE"</xref>
                    or <xref target="LIST MIDI_INPUT_DEVICES">"LIST MIDI_INPUT_DEVICES"</xref>
                    command.</t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending a &lt;CRLF&gt; separated list.
                            Each answer line begins with the information category name
                            followed by a colon and then a space character &lt;SP&gt; and finally
                            the info character string to that info category. As some
                            parameters might allow multiple values, character strings are
                            encapsulated into apostrophes ('). At the moment the following
                            information categories are defined (independent of driver):</t>

                            <t>
                                <list>
                                    <t>DRIVER -
                                        <list>
                                            <t>identifier of the used MIDI input driver, as e.g.
                                            returned by the <xref target="LIST AVAILABLE_MIDI_INPUT_DRIVERS">
                                            "LIST AVAILABLE_MIDI_INPUT_DRIVERS"</xref>
                                            command</t>
                                        </list>
                                    </t>
                                </list>
                                <list>
                                    <t>ACTIVE -
                                        <list>
                                            <t>either true or false, if false then the MIDI device is
                                            inactive and doesn't listen to any incoming MIDI events
                                            and thus doesn't forward them to connected sampler
                                            channels</t>
                                        </list>
                                    </t>
                                </list>
                            </t>
                        </list>
                    </t>

                    <t>The mentioned fields above don't have to be in particular
                    order. The fields above are only those fields which are
                    returned by all MIDI input devices. Every MIDI input driver
                    might have its own, additional driver specific parameters (see
                    <xref target="GET MIDI_INPUT_DRIVER INFO">
                    "GET MIDI_INPUT_DRIVER INFO"</xref> command) which are also returned
                    by this command.</t>

                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "GET MIDI_INPUT_DEVICE INFO 0"</t>
                            <t>S: "DRIVER: ALSA"</t>
                            <t>&nbsp;&nbsp;&nbsp;"ACTIVE: true"</t>
                            <t>&nbsp;&nbsp;&nbsp;"."</t>
                        </list>
                    </t>
                </section>

                <section title="Changing settings of MIDI input devices" anchor="SET MIDI_INPUT_DEVICE_PARAMETER">
                    <t>Use the following command to alter a specific setting of a created MIDI input device:</t>
                    <t>
                        <list>
                            <t>SET MIDI_INPUT_DEVICE_PARAMETER &lt;device-id&gt; &lt;key&gt;=&lt;value&gt;</t>
                        </list>
                    </t>

                    <t>Where &lt;device-id&gt; should be replaced by the numerical ID of the
                    MIDI input device as returned by the
                    <xref target="CREATE MIDI_INPUT_DEVICE">"CREATE MIDI_INPUT_DEVICE"</xref>
                    or <xref target="LIST MIDI_INPUT_DEVICES">"LIST MIDI_INPUT_DEVICES"</xref>
                    command, &lt;key&gt; by the name of the parameter to change and
                    &lt;value&gt; by the new value for this parameter.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>in case setting was successfully changed</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>in case setting was changed successfully, but there are
                                    noteworthy issue(s) related, providing an appropriate
                                    warning code and warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "SET MIDI_INPUT_DEVICE_PARAMETER 0 ACTIVE=false"</t>
                            <t>S: "OK"</t>
                        </list>
                    </t>
                </section>

                <section title="Getting information about a MIDI port" anchor="GET MIDI_INPUT_PORT INFO">
                    <t>Use the following command to get information about a MIDI port:</t>
                    <t>
                        <list>
                            <t>GET MIDI_INPUT_PORT INFO &lt;device-id&gt; &lt;midi-port&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;device-id&gt; is the numerical ID of the MIDI input device as returned by the
                    <xref target="CREATE MIDI_INPUT_DEVICE">"CREATE MIDI_INPUT_DEVICE"</xref>
                    or <xref target="LIST MIDI_INPUT_DEVICES">"LIST MIDI_INPUT_DEVICES"</xref>
                    command and &lt;midi-port&gt; the MIDI input port number.</t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending a &lt;CRLF&gt; separated list.
                            Each answer line begins with the information category name
                            followed by a colon and then a space character &lt;SP&gt; and finally
                            the info character string to that info category. At the moment
                            the following information categories are defined:</t>

                            <t>NAME -
                                <list>
                                    <t>arbitrary character string naming the port</t>
                                </list>
                            </t>
                        </list>
                    </t>

                    <t>The field above is only the one which is returned by all MIDI
                    ports regardless of the MIDI driver and port. Every MIDI port
                    might have its own, additional driver and port specific
                    parameters.</t>

                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "GET MIDI_INPUT_PORT INFO 0 0"</t>
                            <t>S: "NAME: 'Masterkeyboard'"</t>
                            <t>&nbsp;&nbsp;&nbsp;"ALSA_SEQ_BINDINGS: '64:0'"</t>
                            <t>&nbsp;&nbsp;&nbsp;"."</t>
                        </list>
                    </t>
                </section>

                <section title="Getting information about specific MIDI port parameter" anchor="GET MIDI_INPUT_PORT_PARAMETER INFO">
                    <t>Use the following command to get detailed information about specific MIDI port parameter:</t>
                    <t>
                        <list>
                            <t>GET MIDI_INPUT_PORT_PARAMETER INFO &lt;dev-id&gt; &lt;port&gt; &lt;param&gt;</t>
                        </list>
                    </t>

                    <t>Where &lt;dev-id&gt; is the numerical ID of the MIDI input device as returned by the
                    <xref target="CREATE MIDI_INPUT_DEVICE">"CREATE MIDI_INPUT_DEVICE"</xref>
                    or <xref target="LIST MIDI_INPUT_DEVICES">"LIST MIDI_INPUT_DEVICES"</xref>
                    command, &lt;port&gt; the MIDI port number and
                    &lt;param&gt; a specific port parameter name for which information should be
                    obtained (as returned by the <xref target="GET MIDI_INPUT_PORT INFO">
                    "GET MIDI_INPUT_PORT INFO"</xref> command).</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending a &lt;CRLF&gt; separated list.
                            Each answer line begins with the information category name
                            followed by a colon and then a space character &lt;SP&gt; and finally
                            the info character string to that info category. There is
                            information which is always returned, independently of the
                            given channel parameter and there is optional information
                            which are only shown dependently to the given MIDI port. At the
                            moment the following information categories are defined:</t>

                            <t>TYPE -
                                <list>
                                    <t>either "BOOL" for boolean value(s) or "INT" for integer
                                    value(s) or "FLOAT" for dotted number(s) or "STRING" for
                                    character string(s)
                                    (always returned)</t>
                                </list>
                            </t>
                            <t>DESCRIPTION -
                                <list>
                                    <t>arbitrary text describing the purpose of the parameter
                                    (always returned)</t>
                                </list>
                            </t>
                            <t>FIX -
                                <list>
                                    <t>either true or false, if true then this parameter is
                                    read only, thus cannot be altered
                                    (always returned)</t>
                                </list>
                            </t>
                            <t>MULTIPLICITY -
                                <list>
                                    <t>either true or false, defines if this parameter allows
                                    only one value or a list of values, where true means
                                    multiple values and false only a single value allowed
                                    (always returned)</t>
                                </list>
                            </t>
                            <t>RANGE_MIN -
                                <list>
                                    <t>defines lower limit of the allowed value range for this
                                    parameter, can be an integer value as well as a dotted
                                    number, this parameter is usually used in conjunction
                                    with 'RANGE_MAX' but may also appear without
                                    (optionally returned, dependent to driver and port
                                    parameter)</t>
                                </list>
                            </t>
                            <t>RANGE_MAX -
                                <list>
                                    <t>defines upper limit of the allowed value range for this
                                    parameter, can be an integer value as well as a dotted
                                    number, this parameter is usually used in conjunction
                                    with 'RANGE_MIN' but may also appear without
                                    (optionally returned, dependent to driver and port
                                    parameter)</t>
                                </list>
                            </t>
                            <t>POSSIBILITIES -
                                <list>
                                    <t>comma separated list of possible values for this
                                    parameter, character strings are encapsulated into
                                    apostrophes
                                    (optionally returned, dependent to device and port
                                    parameter)</t>
                                </list>
                            </t>
                        </list>
                    </t>

                    <t>The mentioned fields above don't have to be in particular order.</t>

                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "GET MIDI_INPUT_PORT_PARAMETER INFO 0 0 ALSA_SEQ_BINDINGS"</t>
                            <t>S: "DESCRIPTION: bindings to other ALSA sequencer clients"</t>
                            <t>&nbsp;&nbsp;&nbsp;"TYPE: STRING"</t>
                            <t>&nbsp;&nbsp;&nbsp;"FIX: false"</t>
                            <t>&nbsp;&nbsp;&nbsp;"MULTIPLICITY: true"</t>
                            <t>&nbsp;&nbsp;&nbsp;"POSSIBILITIES: '64:0','68:0','68:1'"</t>
                            <t>&nbsp;&nbsp;&nbsp;"."</t>
                        </list>
                    </t>
                </section>

                <section title="Changing settings of MIDI input ports" anchor="SET MIDI_INPUT_PORT_PARAMETER">
                    <t>Use the following command to alter a specific setting of a MIDI input port:</t>
                    <t>
                        <list>
                            <t>SET MIDI_INPUT_PORT_PARAMETER &lt;device-id&gt; &lt;port&gt; &lt;key&gt;=&lt;value&gt;</t>
                        </list>
                    </t>

                    <t>Where &lt;device-id&gt; should be replaced by the numerical ID of the
                    MIDI device as returned by the
                    <xref target="CREATE MIDI_INPUT_DEVICE">"CREATE MIDI_INPUT_DEVICE"</xref>
                    or <xref target="LIST MIDI_INPUT_DEVICES">"LIST MIDI_INPUT_DEVICES"</xref>
                    command, &lt;port&gt; by the MIDI port number, &lt;key&gt; by the name of
                    the parameter to change and &lt;value&gt; by the new value for this
                    parameter.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>in case setting was successfully changed</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>in case setting was changed successfully, but there are
                                    noteworthy issue(s) related, providing an appropriate
                                    warning code and warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>
            </section>

            <section title="Configuring sampler channels">
                <t>The following commands describe how to add and remove sampler channels, associate a
                sampler channel with a sampler engine, load instruments and connect sampler channels to
                MIDI and audio devices.</t>

                <section title="Loading an instrument" anchor="LOAD INSTRUMENT">
                    <t>An instrument file can be loaded and assigned to a sampler channel by one of the following commands:</t>
                    <t>
                        <list>
                            <t>LOAD INSTRUMENT [NON_MODAL] '&lt;filename&gt;' &lt;instr-index&gt; &lt;sampler-channel&gt;</t>
                        </list>
                    </t>

                    <t>Where &lt;filename&gt; is the name of the instrument file on the
                    LinuxSampler instance's host system, &lt;instr-index&gt; the index of the
                    instrument in the instrument file and &lt;sampler-channel> is the
                    number of the sampler channel the instrument should be assigned to.
                    Each sampler channel can only have one instrument.</t>

                    <t>The difference between regular and NON_MODAL versions of the command
                    is that the regular command returns OK only after the instrument has been
                    fully loaded and the channel is ready to be used while NON_MODAL version
                    returns immediately and a background process is launched to load the instrument
                    on the channel. The <xref target="GET CHANNEL INFO">GET CHANNEL INFO</xref>
                    command can be used to obtain loading
                    progress from INSTRUMENT_STATUS field. LOAD command will perform sanity checks
                    such as making sure that the file could be read and it is of a proper format
                    and SHOULD return ERR and SHOULD not launch the background process should any
                    errors be detected at that point.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>in case the instrument was successfully loaded</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>in case the instrument was loaded successfully, but there
                                    are noteworthy issue(s) related (e.g. Engine doesn't support
                                    one or more patch parameters provided by the loaded
                                    instrument file), providing an appropriate warning code and
                                    warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>

                <section title="Loading a sampler engine" anchor="LOAD ENGINE">
                    <t>A sampler engine type can be associated to a specific sampler
                    channel by the following command:</t>
                    <t>
                        <list>
                            <t>LOAD ENGINE &lt;engine-name&gt; &lt;sampler-channel&gt;</t>
                        </list>
                    </t>

                    <t>Where &lt;engine-name&gt; is an engine name as obtained by the
                    <xref target="LIST AVAILABLE_ENGINES">
                    "LIST AVAILABLE_ENGINES"</xref> command and &lt;sampler-channel&gt;
                    the sampler channel as returned by the
                    <xref target="ADD CHANNEL">"ADD CHANNEL"</xref> or
                    <xref target="LIST CHANNELS">"LIST CHANNELS"</xref> command where
                    the engine type should be assigned to. This command should be issued
                    after adding a new sampler channel and before any other control
                    commands on the new sampler channel. It can also be used to change
                    the engine type of a sampler channel. This command has (currently) no
                    way to define or force if a new engine instance should be created and
                    assigned to the given sampler channel or if an already existing
                    instance of that engine type, shared with other sampler channels,
                    should be used.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>in case the engine was successfully deployed</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>in case the engine was deployed successfully, but there
                                    are noteworthy issue(s) related, providing an appropriate
                                    warning code and warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and
                                    error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>

                <section title="Getting all created sampler channel count" anchor="GET CHANNELS">
                    <t>The number of sampler channels can change on runtime. To get the
                    current amount of sampler channels, the front-end can send the
                    following command:</t>
                    <t>
                        <list>
                            <t>GET CHANNELS</t>
                        </list>
                    </t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by returning the current number of sampler channels.</t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "GET CHANNELS"</t>
                            <t>S: "12"</t>
                        </list>
                    </t>
                </section>

                <section title="Getting all created sampler channel list" anchor="LIST CHANNELS">
                    <t>The number of sampler channels can change on runtime. To get the
                    current list of sampler channels, the front-end can send the
                    following command:</t>
                    <t>
                        <list>
                            <t>LIST CHANNELS</t>
                        </list>
                    </t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by returning a comma separated list
                            with all sampler channels numerical IDs.</t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "LIST CHANNELS"</t>
                            <t>S: "0,1,2,3,4,5,6,9,10,11,15,20"</t>
                        </list>
                    </t>
                </section>

                <section title="Adding a new sampler channel" anchor="ADD CHANNEL">
                    <t>A new sampler channel can be added to the end of the sampler
                    channel list by sending the following command:</t>
                    <t>
                        <list>
                            <t>ADD CHANNEL</t>
                        </list>
                    </t>
                    <t>This will increment the sampler channel count by one and the new
                    sampler channel will be appended to the end of the sampler channel
                    list. The front-end should send the respective, related commands
                    right after to e.g. load an engine, load an instrument and setting
                    input, output method and eventually other commands to initialize
                    the new channel. The front-end should use the sampler channel
                    returned by the answer of this command to perform the previously
                    recommended commands, to avoid race conditions e.g. with other
                    front-ends that might also have sent an "ADD CHANNEL" command.</t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK[&lt;sampler-channel&gt;]" -
                                <list>
                                    <t>in case a new sampler channel could be added, where
                                    &lt;sampler-channel&gt; reflects the channel number of the new
                                    created sampler channel which should be used to set up
                                    the sampler channel by sending subsequent initialization
                                    commands</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>in case a new channel was added successfully, but there are
                                    noteworthy issue(s) related, providing an appropriate
                                    warning code and warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and
                                    error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>

                <section title="Removing a sampler channel" anchor="REMOVE CHANNEL">
                    <t>A sampler channel can be removed by sending the following command:</t>
                    <t>
                        <list>
                            <t>REMOVE CHANNEL &lt;sampler-channel&gt;</t>
                        </list>
                    </t>

                    <t>Where &lt;sampler-channel&gt; should be replaced by the
                    number of the sampler channel as given by the
                    <xref target="ADD CHANNEL">"ADD CHANNEL"</xref>
                    or <xref target="LIST CHANNELS">"LIST CHANNELS"</xref>
                    command. The channel numbers of all subsequent sampler channels
                    remain the same.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>in case the given sampler channel could be removed</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>in case the given channel was removed, but there are
                                    noteworthy issue(s) related, providing an appropriate
                                    warning code and warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and
                                    error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>

                <section title="Getting amount of available engines" anchor="GET AVAILABLE_ENGINES">
                    <t>The front-end can ask for the number of available engines by sending the following command:</t>
                    <t>
                        <list>
                            <t>GET AVAILABLE_ENGINES</t>
                        </list>
                    </t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending the number of available engines.</t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "GET AVAILABLE_ENGINES"</t>
                            <t>S: "4"</t>
                        </list>
                    </t>
                </section>

                <section title="Getting all available engines" anchor="LIST AVAILABLE_ENGINES">
                    <t>The front-end can ask for a list of all available engines by sending the following command:</t>
                    <t>
                        <list>
                            <t>LIST AVAILABLE_ENGINES</t>
                        </list>
                    </t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending a comma separated list
                            of the engines' names encapsulated into apostrophes (').
                            Engine names can consist of lower and upper cases,
                            digits and underlines ("_" character).</t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "LIST AVAILABLE_ENGINES"</t>
                            <t>S: "'GigEngine','AkaiEngine','DLSEngine','JoesCustomEngine'"</t>
                        </list>
                    </t>
                </section>

                <section title="Getting information about an engine" anchor="GET ENGINE INFO">
                    <t>The front-end can ask for information about a specific engine by
                    sending the following command:</t>
                    <t>
                        <list>
                            <t>GET ENGINE INFO &lt;engine-name&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;engine-name&gt; is an engine name as obtained by the
                    <xref target="LIST AVAILABLE_ENGINES">
                    "LIST AVAILABLE_ENGINES"</xref> command.</t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending a &lt;CRLF&gt; separated list.
                            Each answer line begins with the information category name
                            followed by a colon and then a space character &lt;SP&gt; and finally
                            the info character string to that info category. At the moment
                            the following categories are defined:</t>

                            <t>
                                <list>
                                    <t>DESCRIPTION -
                                        <list>
                                            <t>arbitrary description text about the engine</t>
                                        </list>
                                    </t>
                                     <t>VERSION -
                                        <list>
                                            <t>arbitrary character string regarding the engine's version</t>
                                        </list>
                                    </t>
                                </list>
                            </t>
                        </list>
                    </t>

                    <t>The mentioned fields above don't have to be in particular order.</t>

                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "GET ENGINE INFO JoesCustomEngine"</t>
                            <t>S: "DESCRIPTION: this is Joe's custom sampler engine"</t>
                            <t>&nbsp;&nbsp;&nbsp;"VERSION: testing-1.0"</t>
                            <t>&nbsp;&nbsp;&nbsp;"."</t>
                        </list>
                    </t>
                </section>

                <section title="Getting sampler channel information" anchor="GET CHANNEL INFO">
                    <t>The front-end can ask for the current settings of a sampler channel
                    by sending the following command:</t>
                    <t>
                        <list>
                            <t>GET CHANNEL INFO &lt;sampler-channel&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;sampler-channel&gt; is the sampler channel number the front-end is interested in
                    as returned by the <xref target="ADD CHANNEL">"ADD CHANNEL"</xref>
                    or <xref target="LIST CHANNELS">"LIST CHANNELS"</xref> command.</t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending a &lt;CRLF&gt; separated list.
                            Each answer line begins with the settings category name
                            followed by a colon and then a space character &lt;SP&gt; and finally
                            the info character string to that setting category. At the
                            moment the following categories are defined:</t>

                            <t>
                                <list>
                                    <t>ENGINE_NAME -
                                        <list>
                                            <t>name of the engine that is associated with the sampler
                                            channel, "NONE" if there's no engine associated yet for
                                            this sampler channel</t>
                                        </list>
                                    </t>
                                    <t>AUDIO_OUTPUT_DEVICE -
                                        <list>
                                            <t>numerical ID of the audio output device which is
                                            currently connected to this sampler channel to output
                                            the audio signal, "NONE" if there's no device
                                            connected to this sampler channel</t>
                                        </list>
                                    </t>
                                    <t>AUDIO_OUTPUT_CHANNELS -
                                        <list>
                                            <t>number of output channels the sampler channel offers
                                            (dependent to used sampler engine and loaded instrument)</t>
                                        </list>
                                    </t>
                                    <t>AUDIO_OUTPUT_ROUTING -
                                        <list>
                                            <t>comma separated list which reflects to which audio
                                            channel of the selected audio output device each
                                            sampler output channel is routed to, e.g. "0,3" would
                                            mean the engine's output channel 0 is routed to channel
                                            0 of the audio output device and the engine's output
                                            channel 1 is routed to the channel 3 of the audio
                                            output device</t>
                                        </list>
                                    </t>
                                    <t>INSTRUMENT_FILE -
                                        <list>
                                            <t>the file name of the loaded instrument, "NONE" if
                                            there's no instrument yet loaded for this sampler
                                            channel</t>
                                        </list>
                                    </t>
                                    <t>INSTRUMENT_NR -
                                        <list>
                                            <t>the instrument index number of the loaded instrument</t>
                                        </list>
                                    </t>
                                    <t>INSTRUMENT_NAME -
                                        <list>
                                            <t>the instrument name of the loaded instrument</t>
                                        </list>
                                    </t>
                                    <t>INSTRUMENT_STATUS -
                                        <list>
                                            <t>integer values 0 to 100 indicating loading progress percentage for the instrument. Negative
                                            value indicates a loading exception. Value of 100 indicates that the instrument is fully
                                            loaded.</t>
                                        </list>
                                    </t>
                                    <t>MIDI_INPUT_DEVICE -
                                        <list>
                                            <t>numerical ID of the MIDI input device which is
                                            currently connected to this sampler channel to deliver
                                            MIDI input commands, "NONE" if there's no device
                                            connected to this sampler channel</t>
                                        </list>
                                    </t>
                                    <t>MIDI_INPUT_PORT -
                                        <list>
                                            <t>port number of the MIDI input device</t>
                                        </list>
                                    </t>
                                    <t>MIDI_INPUT_CHANNEL -
                                        <list>
                                            <t>the MIDI input channel number this sampler channel
                                            should listen to or "ALL" to listen on all MIDI channels</t>
                                        </list>
                                    </t>
                                    <t>VOLUME -
                                        <list>
                                            <t>optionally dotted number for the channel volume factor
                                            (where a value < 1.0 means attenuation and a value >
                                            1.0 means amplification)</t>
                                        </list>
                                    </t>
                                    <t>MUTE -
                                        <list>
                                            <t>Determines whether the channel is muted, "true" if the
                                            channel is muted, "false" if the channel is not muted, and
                                            "MUTED_BY_SOLO" if the channel is muted because of the
                                            presence of a solo channel and will be unmuted when
                                            there are no solo channels left</t>
                                        </list>
                                    </t>
                                    <t>SOLO -
                                        <list>
                                            <t>Determines whether this is a solo channel, "true" if
                                            the channel is a solo channel; "false" otherwise</t>
                                        </list>
                                    </t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>The mentioned fields above don't have to be in particular order.</t>

                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "GET CHANNEL INFO 34"</t>
                            <t>S: "ENGINE_NAME: GigEngine"</t>
                            <t>&nbsp;&nbsp;&nbsp;"VOLUME: 1.0"</t>
                            <t>&nbsp;&nbsp;&nbsp;"AUDIO_OUTPUT_DEVICE: 0"</t>
                            <t>&nbsp;&nbsp;&nbsp;"AUDIO_OUTPUT_CHANNELS: 2"</t>
                            <t>&nbsp;&nbsp;&nbsp;"AUDIO_OUTPUT_ROUTING: 0,1"</t>
                            <t>&nbsp;&nbsp;&nbsp;"INSTRUMENT_FILE: /home/joe/FazioliPiano.gig"</t>
                            <t>&nbsp;&nbsp;&nbsp;"INSTRUMENT_NR: 0"</t>
                            <t>&nbsp;&nbsp;&nbsp;"INSTRUMENT_NAME: Fazioli Piano"</t>
                            <t>&nbsp;&nbsp;&nbsp;"INSTRUMENT_STATUS: 100"</t>
                            <t>&nbsp;&nbsp;&nbsp;"MIDI_INPUT_DEVICE: 0"</t>
                            <t>&nbsp;&nbsp;&nbsp;"MIDI_INPUT_PORT: 0"</t>
                            <t>&nbsp;&nbsp;&nbsp;"MIDI_INPUT_CHANNEL: 5"</t>
                            <t>&nbsp;&nbsp;&nbsp;"."</t>
                        </list>
                    </t>
                </section>

                <section title="Current number of active voices" anchor="GET CHANNEL VOICE_COUNT">
                    <t>The front-end can ask for the current number of active voices on a
                    sampler channel by sending the following command:</t>
                    <t>
                        <list>
                            <t>GET CHANNEL VOICE_COUNT &lt;sampler-channel&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;sampler-channel&gt; is the sampler channel number the front-end is interested in
                    as returned by the <xref target="ADD CHANNEL">"ADD CHANNEL"</xref>
                    or <xref target="LIST CHANNELS">"LIST CHANNELS"</xref> command.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by returning the number of active
                            voices on that channel.</t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>

                <section title="Current number of active disk streams" anchor="GET CHANNEL STREAM_COUNT">
                    <t>The front-end can ask for the current number of active disk streams
                    on a sampler channel by sending the following command:</t>
                    <t>
                        <list>
                            <t>GET CHANNEL STREAM_COUNT &lt;sampler-channel&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;sampler-channel&gt; is the sampler channel number the front-end is interested in
                    as returned by the <xref target="ADD CHANNEL">"ADD CHANNEL"</xref>
                    or <xref target="LIST CHANNELS">"LIST CHANNELS"</xref> command.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by returning the number of active
                            disk streams on that channel in case the engine supports disk
                            streaming, if the engine doesn't support disk streaming it will
                            return "NA" for not available.</t>
                        </list>
                    </t>
                    <t>Example:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>

                <section title="Current fill state of disk stream buffers" anchor="GET CHANNEL BUFFER_FILL">
                    <t>The front-end can ask for the current fill state of all disk streams
                    on a sampler channel by sending the following command:</t>
                    <t>
                        <list>
                            <t>GET CHANNEL BUFFER_FILL BYTES &lt;sampler-channel&gt;</t>
                        </list>
                    </t>
                    <t>to get the fill state in bytes or</t>
                    <t>
                        <list>
                            <t>GET CHANNEL BUFFER_FILL PERCENTAGE &lt;sampler-channel&gt;</t>
                        </list>
                    </t>
                    <t>to get the fill state in percent, where &lt;sampler-channel&gt; is the
                    sampler channel number the front-end is interested in
                    as returned by the <xref target="ADD CHANNEL">"ADD CHANNEL"</xref>
                    or <xref target="LIST CHANNELS">"LIST CHANNELS"</xref> command.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will either answer by returning a comma separated
                            string with the fill state of all disk stream buffers on that
                            channel or an empty line if there are no active disk streams or
                            "NA" for *not available* in case the engine which is deployed
                            doesn't support disk streaming. Each entry in the answer list
                            will begin with the stream's ID in brackets followed by the
                            numerical representation of the fill size (either in bytes or
                            percentage). Note: due to efficiency reasons the fill states in
                            the response are not in particular order, thus the front-end has
                            to sort them by itself if necessary.</t>
                        </list>
                    </t>
                    <t>Examples:</t>
                    <t>
                        <list>
                            <t>C: "GET CHANNEL BUFFER_FILL BYTES 4"</t>
                            <t>S: "[115]420500,[116]510300,[75]110000,[120]230700"</t>
                        </list>

                        <list>
                            <t>C: "GET CHANNEL BUFFER_FILL PERCENTAGE 4"</t>
                            <t>S: "[115]90%,[116]98%,[75]40%,[120]62%"</t>
                        </list>

                        <list>
                            <t>C: "GET CHANNEL BUFFER_FILL PERCENTAGE 4"</t>
                            <t>S: ""</t>
                        </list>
                    </t>
                </section>

                <section title="Setting audio output device" anchor="SET CHANNEL AUDIO_OUTPUT_DEVICE">
                    <t>The front-end can set the audio output device on a specific sampler
                    channel by sending the following command:</t>
                    <t>
                        <list>
                            <t>SET CHANNEL AUDIO_OUTPUT_DEVICE &lt;sampler-channel&gt; &lt;audio-device-id&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;sampler-channel&gt; is the respective sampler channel
                    number as returned by the <xref target="ADD CHANNEL">"ADD CHANNEL"</xref>
                    or <xref target="LIST CHANNELS">"LIST CHANNELS"</xref> command and
                    &lt;audio-device-id&gt; is the numerical ID of the audio output device as given by the
                    <xref target="CREATE AUDIO_OUTPUT_DEVICE">"CREATE AUDIO_OUTPUT_DEVICE"</xref>
                    or <xref target="LIST AUDIO_OUTPUT_DEVICES">"LIST AUDIO_OUTPUT_DEVICES"</xref>
                    command.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>on success</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>if audio output device was set, but there are noteworthy
                                    issue(s) related, providing an appropriate warning code and
                                    warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Examples:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>

                <section title="Setting audio output type" anchor="SET CHANNEL AUDIO_OUTPUT_TYP">
                    <t>DEPRECATED: THIS COMMAND WILL DISAPPEAR SOON!</t>

                    <t>The front-end can alter the audio output type on a specific sampler
                    channel by sending the following command:</t>
                    <t>
                        <list>
                            <t>SET CHANNEL AUDIO_OUTPUT_TYPE &lt;sampler-channel&gt; &lt;audio-output-type&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;audio-output-type&gt; is currently either "ALSA" or "JACK" and
                    &lt;sampler-channel&gt; is the respective sampler channel number.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>on success</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>if audio output type was set, but there are noteworthy
                                    issue(s) related, providing an appropriate warning code and
                                    warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Examples:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>

                <section title="Setting audio output channel" anchor="SET CHANNEL AUDIO_OUTPUT_CHANNEL">
                    <t>The front-end can alter the audio output channel on a specific
                    sampler channel by sending the following command:</t>
                    <t>
                        <list>
                            <t>SET CHANNEL AUDIO_OUTPUT_CHANNEL &lt;sampler-chan&gt; &lt;audio-out&gt; &lt;audio-in&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;sampler-chan&gt; is the sampler channel number
                    as returned by the <xref target="ADD CHANNEL">"ADD CHANNEL"</xref>
                    or <xref target="LIST CHANNELS">"LIST CHANNELS"</xref> command, &lt;audio-out&gt; is the
                    numerical ID of the sampler channel's audio output channel which should be
                    rerouted and &lt;audio-in&gt; is the numerical ID of the audio channel of the selected audio
                    output device where &lt;audio-out&gt; should be routed to.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>on success</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>if audio output channel was set, but there are noteworthy
                                    issue(s) related, providing an appropriate warning code and
                                    warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Examples:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>

                <section title="Setting MIDI input device" anchor="SET CHANNEL MIDI_INPUT_DEVICE">
                    <t>The front-end can set the MIDI input device on a specific sampler
                    channel by sending the following command:</t>
                    <t>
                        <list>
                            <t>SET CHANNEL MIDI_INPUT_DEVICE &lt;sampler-channel&gt; &lt;midi-device-id&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;sampler-channel&gt; is the sampler channel number
                    as returned by the <xref target="ADD CHANNEL">"ADD CHANNEL"</xref>
                    or <xref target="LIST CHANNELS">"LIST CHANNELS"</xref> command
                    and &lt;midi-device-id&gt; is  the numerical ID of the MIDI input device as returned by the
                    <xref target="CREATE MIDI_INPUT_DEVICE">"CREATE MIDI_INPUT_DEVICE"</xref>
                    or <xref target="LIST MIDI_INPUT_DEVICES">"LIST MIDI_INPUT_DEVICES"</xref> command.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>on success</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>if MIDI input device was set, but there are noteworthy
                                    issue(s) related, providing an appropriate warning code and
                                    warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Examples:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>

                <section title="Setting MIDI input type" anchor="SET CHANNEL MIDI_INPUT_TYPE">
                    <t>DEPRECATED: THIS COMMAND WILL DISAPPEAR SOON!</t>

                    <t>The front-end can alter the MIDI input type on a specific sampler
                    channel by sending the following command:</t>
                    <t>
                        <list>
                            <t>SET CHANNEL MIDI_INPUT_TYPE &lt;sampler-channel&gt; &lt;midi-input-type&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;midi-input-type&gt; is currently only "ALSA" and
                    &lt;sampler-channel&gt; is the respective sampler channel number.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>on success</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>if MIDI input type was set, but there are noteworthy
                                    issue(s) related, providing an appropriate warning code and
                                    warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Examples:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>

                <section title="Setting MIDI input port" anchor="SET CHANNEL MIDI_INPUT_PORT">
                    <t>The front-end can alter the MIDI input port on a specific sampler
                    channel by sending the following command:</t>
                    <t>
                        <list>
                            <t>SET CHANNEL MIDI_INPUT_PORT &lt;sampler-channel&gt; &lt;midi-input-port&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;midi-input-port&gt; is a MIDI input port number of the
                    MIDI input device connected to the sampler channel given by
                    &lt;sampler-channel&gt;.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>on success</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>if MIDI input port was set, but there are noteworthy
                                    issue(s) related, providing an appropriate warning code and
                                    warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Examples:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>

                <section title="Setting MIDI input channel" anchor="SET CHANNEL MIDI_INPUT_CHANNEL">
                    <t>The front-end can alter the MIDI channel a sampler channel should
                    listen to by sending the following command:</t>
                    <t>
                        <list>
                            <t>SET CHANNEL MIDI_INPUT_CHANNEL &lt;sampler-channel&gt; &lt;midi-input-chan&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;midi-input-chan&gt; is the number of the new MIDI input channel where
                    &lt;sampler-channel&gt; should listen to or "ALL" to listen on all 16 MIDI
                    channels.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>on success</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>if MIDI input channel was set, but there are noteworthy
                                    issue(s) related, providing an appropriate warning code and
                                    warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Examples:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>

                <section title="Setting channel volume" anchor="SET CHANNEL VOLUME">
                    <t>The front-end can alter the volume of a sampler channel by sending
                    the following command:</t>
                    <t>
                        <list>
                            <t>SET CHANNEL VOLUME &lt;sampler-channel&gt; &lt;volume&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;volume&gt; is an optionally dotted positive number (a value
                    smaller than 1.0 means attenuation, whereas a value greater than
                    1.0 means amplification) and &lt;sampler-channel&gt; defines the sampler
                    channel where this volume factor should be set.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>on success</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>if channel volume was set, but there are noteworthy
                                    issue(s) related, providing an appropriate warning code and
                                    warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Examples:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>

                <section title="Muting a sampler channel" anchor="SET CHANNEL MUTE">
                    <t>The front-end can mute/unmute a specific sampler
                    channel by sending the following command:</t>
                    <t>
                        <list>
                            <t>SET CHANNEL MUTE &lt;sampler-channel&gt; &lt;mute&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;sampler-channel&gt; is the respective sampler channel
                    number as returned by the <xref target="ADD CHANNEL">"ADD CHANNEL"</xref>
                    or <xref target="LIST CHANNELS">"LIST CHANNELS"</xref> command and
                    &lt;mute&gt; should be replaced either by "1" to mute the channel or "0"
                    to unmute the channel.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>on success</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>if the channel was muted/unmuted, but there are noteworthy
                                    issue(s) related, providing an appropriate warning code and
                                    warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Examples:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>

                <section title="Soloing a sampler channel" anchor="SET CHANNEL SOLO">
                    <t>The front-end can solo/unsolo a specific sampler channel
                    by sending the following command:</t>
                    <t>
                        <list>
                            <t>SET CHANNEL SOLO &lt;sampler-channel&gt; &lt;solo&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;sampler-channel&gt; is the respective sampler channel
                    number as returned by the <xref target="ADD CHANNEL">"ADD CHANNEL"</xref>
                    or <xref target="LIST CHANNELS">"LIST CHANNELS"</xref> command and
                    &lt;solo&gt; should be replaced either by "1" to solo the channel or "0"
                    to unsolo the channel.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>on success</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>if the channel was soloed/unsoloed, but there are noteworthy
                                    issue(s) related, providing an appropriate warning code and
                                    warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Examples:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>

                <section title="Resetting a sampler channel" anchor="RESET CHANNEL">
                    <t>The front-end can reset a particular sampler channel by sending the following command:</t>
                    <t>
                        <list>
                            <t>RESET CHANNEL &lt;sampler-channel&gt;</t>
                        </list>
                    </t>
                    <t>
                    Where &lt;sampler-channel&gt; defines the sampler channel to be reset.
                    This will cause the engine on that sampler channel, its voices and
                    eventually disk streams and all control and status variables to be
                    reset.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>on success</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>if channel was reset, but there are noteworthy issue(s)
                                    related, providing an appropriate warning code and warning
                                    message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and
                                    error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Examples:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>
            </section>

            <section title="Controlling connection">
                <t>The following commands are used to control the connection to LinuxSampler.</t>

                <section title="Register front-end for receiving event messages" anchor="SUBSCRIBE">
                    <t>The front-end can register itself to the LinuxSampler application to
                    be informed about noteworthy events by sending this command:</t>
                    <t>
                        <list>
                            <t>SUBSCRIBE &lt;event-id&gt;</t>
                        </list>
                    </t>
                    <t>where &lt;event-id&gt; will be replaced by the respective event that
                    client wants to subscribe to.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>on success</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>if registration succeeded, but there are noteworthy
                                    issue(s) related, providing an appropriate warning code and
                                    warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and
                                    error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Examples:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>

                <section title="Unregister front-end for not receiving event messages" anchor="UNSUBSCRIBE">
                    <t>The front-end can unregister itself if it doesn't want to receive event
                    messages anymore by sending the following command:</t>
                    <t>
                        <list>
                            <t>UNSUBSCRIBE &lt;event-id&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;event-id&gt; will be replaced by the respective event that
                    client doesn't want to receive anymore.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>on success</t>
                                </list>
                            </t>
                            <t>"WRN:&lt;warning-code&gt;:&lt;warning-message&gt;" -
                                <list>
                                    <t>if unregistration succeeded, but there are noteworthy
                                    issue(s) related, providing an appropriate warning code and
                                    warning message</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>in case it failed, providing an appropriate error code and
                                    error message</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Examples:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>

                <section title="Enable or disable echo of commands" anchor="SET ECHO">
                    <t>To enable or disable back sending of commands to the client the following command can be used:</t>
                    <t>
                        <list>
                            <t>SET ECHO &lt;value&gt;</t>
                        </list>
                    </t>
                    <t>Where &lt;value&gt; should be replaced either by "1" to enable echo mode
                    or "0" to disable echo mode. When echo mode is enabled, all
                    commands send to LinuxSampler will be immediately send back and
                    after this echo the actual response to the command will be
                    returned. Echo mode will only be altered for the client connection
                    that issued the "SET ECHO" command, not globally for all client
                    connections.</t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>usually</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>on syntax error, e.g. non boolean value</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Examples:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>

                <section title="Close client connection" anchor="QUIT">
                    <t>The client can close its network connection to LinuxSampler by sending the following command:</t>
                    <t>
                        <list>
                            <t>QUIT</t>
                        </list>
                    </t>
                    <t>This is probably more interesting for manual telnet connections to
                    LinuxSampler than really useful for a front-end implementation.</t>
                </section>
            </section>

            <section title="Global commands">
                <t>The following commands have global impact on the sampler.</t>

                <section title="Current number of active voices" anchor="GET TOTAL_VOICE_COUNT">
                    <t>The front-end can ask for the current number of active voices on
                    the sampler by sending the following command:</t>
                    <t>
                        <list>
                            <t>GET TOTAL_VOICE_COUNT</t>
                        </list>
                    </t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by returning the number of all active
                            voices on the sampler.</t>
                        </list>
                    </t>
                </section>

                <section title="Maximum amount of active voices" anchor="GET TOTAL_VOICE_COUNT_MAX">
                    <t>The front-end can ask for the maximum number of active voices
                    by sending the following command:</t>
                    <t>
                        <list>
                            <t>GET TOTAL_VOICE_COUNT_MAX</t>
                        </list>
                    </t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by returning the maximum number
                            of active voices.</t>
                        </list>
                    </t>
                </section>

                <section title="Reset sampler" anchor="RESET">
                    <t>The front-end can reset the whole sampler by sending the following command:</t>
                    <t>
                        <list>
                            <t>RESET</t>
                        </list>
                    </t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>always</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>Examples:</t>
                    <t>
                        <list>
                            <t></t>
                        </list>
                    </t>
                </section>

                <section title="General sampler informations" anchor="GET SERVER INFO">
                    <t>The client can ask for general informations about the LinuxSampler
                       instance by sending the following command:</t>
                    <t>
                        <list>
                            <t>GET SERVER INFO</t>
                        </list>
                    </t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending a &lt;CRLF&gt; separated list.
                               Each answer line begins with the information category name
                               followed by a colon and then a space character &lt;SP&gt; and finally
                               the info character string to that information category. At the
                               moment the following categories are defined:
                            </t>
                            <t>
                                <list>
                                    <t>DESCRIPTION -
                                        <list>
                                            <t>arbitrary textual description about the sampler</t>
                                        </list>
                                    </t>
                                    <t>VERSION -
                                        <list>
                                            <t>version of the sampler</t>
                                        </list>
                                    </t>
                                    <t>PROTOCOL_VERSION -
                                        <list>
                                            <t>version of the LSCP specification the sampler
                                            complies with (see <xref target="LSCP versioning" /> for details)</t>
                                        </list>
                                    </t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>The mentioned fields above don't have to be in particular order.
                    Other fields might be added in future.</t>
                </section>
            </section>


            <section title="MIDI Instrument Mapping">
                <t>The MIDI protocol provides a way to switch between instruments
                by sending so called MIDI bank select and MIDI program change
                messages which are essentially just numbers. The following commands
                allow to actually map arbitrary MIDI bank select / program change
                numbers with real instruments.</t>
                <t>By default, that is when the sampler is launched, this map will
                be empty, thus the sampler will simply ignore all program change
                messages. The front-end has to explicitly add entries to the map
                so the sampler knows how to react on a given program change
                message, that is by switching to the respectively defined engine
                type and loading the respective instrument.</t>
                <t>Also note per MIDI specification a bank select message does not
                cause to switch to another instrument. Instead when receiving a
                bank select message the bank value will be stored and a subsequent
                program change message (which may occur at any time) will finally
                cause the sampler to switch to the respective instrument as
                reflected by the current MIDI instrument map.</t>

                <section title="Create or replace a MIDI instrument map entry" anchor="MAP MIDI_INSTRUMENT">
                    <t>The front-end can create a new or replace an existing entry
                    in the sampler's MIDI instrument map by sending the following
                    command:</t>
                    <t>
                        <list>
                            <t>MAP MIDI_INSTRUMENT &lt;midi_bank_msb&gt;
                            &lt;midi_bank_lsb&gt; &lt;midi_prog&gt; &lt;engine_name&gt;
                            &lt;filename&gt; &lt;instrument_index&gt; &lt;volume_value&gt;
                            [&lt;instr_load_mode&gt;] [&lt;name&gt;]</t>
                        </list>
                    </t>
                    <t>Where &lt;midi_bank_msb&gt; is an integer value between
                    0..127 reflecting the MIDI bank select MSB (coarse) index,
                    &lt;midi_bank_lsb&gt; an integer value between 0..127 reflecting
                    the MIDI bank select LSB (fine) index, &lt;midi_prog&gt; an
                    integer value between 0..127 reflecting the MIDI program change
                    index, &lt;engine_name&gt; a sampler engine name as returned by
                    the <xref target="LIST AVAILABLE_ENGINES">"LIST AVAILABLE_ENGINES"</xref>
                    command (not encapsulated into apostrophes), &lt;filename&gt; the name
                    of the instrument's file to be deployed (encapsulated into apostrophes), &lt;instrument_index&gt; the index (integer value) of the instrument
                    within the given file, &lt;volume_value&gt; reflects the master
                    volume of the instrument as optionally dotted number (where a
                    value < 1.0 means attenuation and a value > 1.0 means
                    amplification). This parameter easily allows to adjust the
                    volume of all intruments within a custom instrument map
                    without having to adjust their instrument files. The
                    OPTIONAL &lt;instr_load_mode&gt; argument defines the life
                    time of the instrument, that is when the instrument should
                    be loaded, when freed and has exactly the following
                    possibilities:</t>
                    <t>
                        <list>
                            <t>"ON_DEMAND" -
                                <list>
                                    <t>The instrument will be loaded when needed,
                                    that is when demanded by at least one sampler
                                    channel. It will immediately be freed from memory
                                    when not needed by any sampler channel anymore.</t>
                                </list>
                            </t>
                            <t>"ON_DEMAND_HOLD" -
                                <list>
                                    <t>The instrument will be loaded when needed,
                                    that is when demanded by at least one sampler
                                    channel. It will be kept in memory even when
                                    not needed by any sampler channel anymore.
                                    Instruments with this mode are only freed
                                    when the sampler is reset or all mapping
                                    entries with this mode (and respective
                                    instrument) are explicitly changed to
                                    "ON_DEMAND" and no sampler channel is using
                                    the instrument anymore.</t>
                                </list>
                            </t>
                            <t>"PERSISTENT" -
                                <list>
                                    <t>The instrument will immediately be loaded
                                    into memory in the background when this mapping
                                    command is sent and the instrument is kept all
                                    the time. Instruments with this mode are
                                    only freed when the sampler is reset or all
                                    mapping entries with this mode (and
                                    respective instrument) are explicitly
                                    changed to "ON_DEMAND" and no sampler
                                    channel is using the instrument anymore.</t>
                                </list>
                            </t>
                            <t>not supplied -
                                <list>
                                    <t>In case there is no &lt;instr_load_mode&gt;
                                    argument given, it will be up to the
                                    InstrumentManager to decide which mode to use.
                                    Usually it will use "ON_DEMAND" if an entry
                                    for the given instrument does not exist in
                                    the InstrumentManager's list yet, otherwise
                                    if an entry already exists, it will simply
                                    stick with the mode currently reflected by
                                    the already existing entry, that is it will
                                    not change the mode.</t>
                                </list>
                            </t>
                        </list>
                    </t>
                    <t>
                    The &lt;instr_load_mode&gt; argument thus allows to define an
                    appropriate strategy (low memory consumption vs. fast
                    instrument switching) for each instrument individually. Note, the
                    following restrictions apply to this argument: "ON_DEMAND_HOLD" and
                    "PERSISTENT" have to be supported by the respective sampler engine
                    (which is technically the case when the engine provides an
                    InstrumentManager for its format). If this is not the case the
                    argument will automatically fall back to the default value
                    "ON_DEMAND". Also the load mode of one instrument may
                    automatically change the laod mode of other instrument(s), i.e.
                    because the instruments are part of the same file and the
                    engine does not allow a way to manage load modes for them
                    individually. Due to this, in case the frontend shows the
                    load modes of entries, the frontend should retrieve the actual
                    mode by i.e. sending
                    <xref target="GET MIDI_INSTRUMENT INFO">"GET MIDI_INSTRUMENT INFO"</xref>
                    command(s). Finally the OPTIONAL &lt;name&gt; argument allows to
                    set a custom name (encapsulated into apostrophes) for the mapping
                    entry, useful for frontends for displaying an appropriate name for
                    mapped instruments (using
                    <xref target="GET MIDI_INSTRUMENT INFO">"GET MIDI_INSTRUMENT INFO"</xref>).
                    </t>
                    <t>
                    The "MAP MIDI_INSTRUMENT" command
                    will immediately return, thus it will not block when an
                    instrument is to be loaded due to a "PERSISTENT" type
                    entry as instruments are loaded in the background. As a
                    consequence this command may not necessarily return an error
                    i.e. when the given instrument file does not exist or may
                    turn out to be corrupt.
                    </t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>usually</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>when the given engine does not exist or a value
                                    is out of range</t>
                                </list>
                            </t>
                        </list>
                    </t>

                    <t>Examples:</t>
                    <t>
                        <list>
                            <t>C: "MAP MIDI_INSTRUMENT 3 0 0 gig '/usr/share/Steinway D.gig' 0 0.8 PERSISTENT"</t>
                            <t>S: "OK"</t>
                        </list>
                    </t>
                    <t>
                        <list>
                            <t>C: "MAP MIDI_INSTRUMENT 127 4 50 gig '/home/john/foostrings.gig' 7 1.0"</t>
                            <t>S: "OK"</t>
                        </list>
                    </t>
                    <t>
                        <list>
                            <t>C: "MAP MIDI_INSTRUMENT 0 0 0 gig '/usr/share/piano.gig' 0 1.0 'Normal Piano'"</t>
                            <t>S: "OK"</t>
                            <t>C: "MAP MIDI_INSTRUMENT 1 0 0 gig '/usr/share/piano.gig' 0 0.25 'Silent Piano'"</t>
                            <t>S: "OK"</t>
                        </list>
                    </t>
                    <t>
                        <list>
                            <t>C: "MAP MIDI_INSTRUMENT 99 8 120 gig '/home/joe/foodrums.gig' 0 1.0 PERSISTENT 'Foo Drumkit'"</t>
                            <t>S: "OK"</t>
                        </list>
                    </t>
                </section>

                <section title="Getting ammount of MIDI instrument map entries" anchor="GET MIDI_INSTRUMENTS">
                    <t>The front-end can query the amount of currently existing MIDI
                    instrument map entries by sending the following
                    command:</t>
                    <t>
                        <list>
                            <t>GET MIDI_INSTRUMENTS</t>
                        </list>
                    </t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending the current number of
                            entries in the sampler's MIDI instrument map.</t>
                        </list>
                    </t>

                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "GET MIDI_INSTRUMENTS"</t>
                            <t>S: "634"</t>
                        </list>
                    </t>
                </section>

                <section title="Getting indeces of all MIDI instrument map entries" anchor="LIST MIDI_INSTRUMENTS">
                    <t>The front-end can query a list of all currently existing MIDI
                    instrument map entries by sending the following command:</t>
                    <t>
                        <list>
                            <t>LIST MIDI_INSTRUMENTS</t>
                        </list>
                    </t>
                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending a comma separated
                            list of MIDI bank MSB (coarse) - MIDI bank LSB (fine) -
                            MIDI program triples, where each triple is encapsulated
                            into curly braces. The list is returned in one single
                            line. Each triple just reflects the key of the respective
                            map entry, thus subsequent
                            <xref target="GET MIDI_INSTRUMENT INFO">"GET MIDI_INSTRUMENT INFO"</xref>
                            command(s) are necessary to retrieve detailed informations
                            about each entry.</t>
                        </list>
                    </t>

                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "LIST MIDI_INSTRUMENTS"</t>
                            <t>S: "{0,0,0},{0,0,1},{120,0,3},{120,0,4},{23,127,127}"</t>
                        </list>
                    </t>
                </section>

                <section title="Remove an entry from the MIDI instrument map" anchor="UNMAP MIDI_INSTRUMENT">
                    <t>The front-end can delete an entry from the MIDI instrument
                    map by sending the following command:</t>
                    <t>
                        <list>
                            <t>UNMAP MIDI_INSTRUMENT &lt;midi_bank_msb&gt; &lt;midi_bank_lsb&gt; &lt;midi_prog&gt;</t>
                        </list>
                    </t>
                    <t>
                    Where &lt;midi_bank_msb&gt; is an integer value between 0..127
                    reflecting the MIDI bank MSB (coarse) value, &lt;midi_bank_lsb&gt;
                    an integer value between 0..127 reflecting the MIDI bank LSB
                    (fine) value and &lt;midi_prog&gt; an integer value between
                    0..127 reflecting the MIDI program value of the map entrie's key
                    index triple.
                    </t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>usually</t>
                                </list>
                            </t>
                            <t>"ERR:&lt;error-code&gt;:&lt;error-message&gt;" -
                                <list>
                                    <t>when index out of bounds</t>
                                </list>
                            </t>
                        </list>
                    </t>

                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "UNMAP MIDI_INSTRUMENT 2 40 127"</t>
                            <t>S: "OK"</t>
                        </list>
                    </t>
                </section>

                <section title="Get current settings of MIDI instrument map entry" anchor="GET MIDI_INSTRUMENT INFO">
                    <t>The front-end can retrieve the current settings of a certain
                    instrument map entry by sending the following command:</t>
                    <t>
                        <list>
                            <t>GET MIDI_INSTRUMENT INFO &lt;midi_bank_msb&gt; &lt;midi_bank_lsb&gt; &lt;midi_prog&gt;</t>
                        </list>
                    </t>
                    <t>
                    Where &lt;midi_bank_msb&gt; is an integer value between 0..127
                    reflecting the MIDI bank MSB (coarse) value, &lt;midi_bank_lsb&gt;
                    an integer value between 0..127 reflecting the MIDI bank LSB
                    (fine) value and &lt;midi_prog&gt; an integer value between
                    0..127 reflecting the MIDI program value of the map entrie's key
                    index triple.
                    </t>

                    <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>LinuxSampler will answer by sending a &lt;CRLF&gt;
                            separated list. Each answer line begins with the
                            information category name followed by a colon and then
                            a space character &lt;SP&gt; and finally the info
                            character string to that info category. At the moment
                            the following categories are defined:</t>
                            <t>"NAME" -
                                <list>
                                    <t>Name for this MIDI instrument map entry (if defined).
                                    This name shall be used by frontends for displaying a
                                    name for this mapped instrument. It can be set and
                                    changed with the
                                    <xref target="MAP MIDI_INSTRUMENT">"MAP MIDI_INSTRUMENT"</xref>
                                    command and does not have to be unique.</t>
                                </list>
                            </t>
                            <t>"ENGINE_NAME" -
                                <list>
                                    <t>Name of the engine to be deployed for this
                                    instrument.</t>
                                </list>
                            </t>
                            <t>"INSTRUMENT_FILE" -
                                <list>
                                    <t>File name of the instrument.</t>
                                </list>
                            </t>
                            <t>"INSTRUMENT_NR" -
                                <list>
                                    <t>Index of the instrument within the file.</t>
                                </list>
                            </t>
                            <t>"INSTRUMENT_NAME" -
                                <list>
                                    <t>Name of the loaded instrument as reflected by its file.
                                    In contrast to the "NAME" field, the "INSTRUMENT_NAME" field
                                    cannot be changed.</t>
                                </list>
                            </t>
                            <t>"LOAD_MODE" -
                                <list>
                                    <t>Life time of instrument
                                    (see <xref target="MAP MIDI_INSTRUMENT">"MAP MIDI_INSTRUMENT"</xref> for details about this setting).</t>
                                </list>
                            </t>
                            <t>"VOLUME" -
                                <list>
                                    <t>master volume of the instrument as optionally
                                    dotted number (where a value < 1.0 means attenuation
                                    and a value > 1.0 means amplification)</t>
                                </list>
                            </t>
                            <t>The mentioned fields above don't have to be in particular order.</t>
                        </list>
                    </t>

                    <t>Example:</t>
                    <t>
                        <list>
                            <t>C: "GET MIDI_INSTRUMENT INFO 3 45 120"</t>
                            <t>S: "NAME: Drums for Foo Song"</t>
                            <t>&nbsp;&nbsp;&nbsp;"ENGINE_NAME: GigEngine"</t>
                            <t>&nbsp;&nbsp;&nbsp;"INSTRUMENT_FILE: /usr/share/joesdrumkit.gig"</t>
                            <t>&nbsp;&nbsp;&nbsp;"INSTRUMENT_NR: 0"</t>
                            <t>&nbsp;&nbsp;&nbsp;"INSTRUMENT_NAME: Joe's Drumkit"</t>
                            <t>&nbsp;&nbsp;&nbsp;"LOAD_MODE: PERSISTENT"</t>
                            <t>&nbsp;&nbsp;&nbsp;"VOLUME: 1.0"</t>
                            <t>&nbsp;&nbsp;&nbsp;"."</t>
                        </list>
                    </t>
                </section>

                <section title="Clear MIDI instrument map" anchor="CLEAR MIDI_INSTRUMENTS">
                    <t>The front-end can clear the whole MIDI instrument map, that
                    is delete all entries by sending the following command:</t>
                    <t>
                        <list>
                            <t>CLEAR MIDI_INSTRUMENTS</t>
                        </list>
                    </t>

                   <t>Possible Answers:</t>
                    <t>
                        <list>
                            <t>"OK" -
                                <list>
                                    <t>always</t>
                                </list>
                            </t>
                        </list>
                    </t>

                    <t>Example:</t>
                    <t>
                       <list>
                            <t>C: "CLEAR MIDI_INSTRUMENTS"</t>
                            <t>S: "OK"</t>
                        </list>
                    </t>
                </section>
            </section>

        </section>


        <section title="Command Syntax" anchor="command_syntax">
            <t>The grammar of the control protocol as descibed in <xref target="control_commands"/>
            is defined below using Backus-Naur Form (BNF as described in <xref target="RFC2234"/>)
            where applicable.
            </t>
            <!--
                This section is automatically generated by scripts/update_grammar.pl
                from src/network/lscp.y (yacc input file). Do not modify this section
                manually !
            -->
            <!-- GRAMMAR_BNF_BEGIN - do NOT delete or modify this line !!! -->

<t>input =
        <list>
                <t>line LF
                </t>
                <t>/ line CR LF
                </t>
        </list>
</t>
<t>line =
        <list>
                <t>/* epsilon (empty line ignored) */
                </t>
                <t>/ comment
                </t>
                <t>/ command
                </t>
                <t>/ error
                </t>
        </list>
</t>
<t>comment =
        <list>
                <t>'#'
                </t>
                <t>/ comment '#'
                </t>
                <t>/ comment SP
                </t>
                <t>/ comment number
                </t>
                <t>/ comment string
                </t>
        </list>
</t>
<t>command =
        <list>
                <t>ADD SP CHANNEL
                </t>
                <t>/ MAP SP map_instruction
                </t>
                <t>/ UNMAP SP unmap_instruction
                </t>
                <t>/ GET SP get_instruction
                </t>
                <t>/ CREATE SP create_instruction
                </t>
                <t>/ DESTROY SP destroy_instruction
                </t>
                <t>/ LIST SP list_instruction
                </t>
                <t>/ LOAD SP load_instruction
                </t>
                <t>/ REMOVE SP remove_instruction

                </t>
                <t>/ SET SP set_instruction
                </t>
                <t>/ SUBSCRIBE SP subscribe_event
                </t>
                <t>/ UNSUBSCRIBE SP unsubscribe_event
                </t>
                <t>/ SELECT SP text
                </t>
                <t>/ RESET SP reset_instruction
                </t>
                <t>/ CLEAR SP clear_instruction
                </t>
                <t>/ RESET
                </t>
                <t>/ QUIT
                </t>
        </list>
</t>
<t>subscribe_event =
        <list>
                <t>CHANNEL_COUNT
                </t>
                <t>/ VOICE_COUNT
                </t>
                <t>/ STREAM_COUNT
                </t>
                <t>/ BUFFER_FILL
                </t>
                <t>/ CHANNEL_INFO
                </t>
                <t>/ MISCELLANEOUS
                </t>
                <t>/ TOTAL_VOICE_COUNT
                </t>
        </list>
</t>
<t>unsubscribe_event =
        <list>
                <t>CHANNEL_COUNT
                </t>
                <t>/ VOICE_COUNT
                </t>
                <t>/ STREAM_COUNT
                </t>
                <t>/ BUFFER_FILL
                </t>
                <t>/ CHANNEL_INFO
                </t>
                <t>/ MISCELLANEOUS
                </t>
                <t>/ TOTAL_VOICE_COUNT
                </t>
        </list>
</t>
<t>map_instruction =
        <list>
                <t>MIDI_INSTRUMENT SP midi_bank_msb SP midi_bank_lsb SP midi_prog SP engine_name SP filename SP instrument_index SP volume_value
                </t>
                <t>/ MIDI_INSTRUMENT SP midi_bank_msb SP midi_bank_lsb SP midi_prog SP engine_name SP filename SP instrument_index SP volume_value SP instr_load_mode
                </t>
                <t>/ MIDI_INSTRUMENT SP midi_bank_msb SP midi_bank_lsb SP midi_prog SP engine_name SP filename SP instrument_index SP volume_value SP entry_name
                </t>
                <t>/ MIDI_INSTRUMENT SP midi_bank_msb SP midi_bank_lsb SP midi_prog SP engine_name SP filename SP instrument_index SP volume_value SP instr_load_mode SP entry_name
                </t>
        </list>
</t>
<t>unmap_instruction =
        <list>
                <t>MIDI_INSTRUMENT SP midi_bank_msb SP midi_bank_lsb SP midi_prog
                </t>
        </list>
</t>
<t>remove_instruction =
        <list>
                <t>CHANNEL SP sampler_channel
                </t>
        </list>
</t>
<t>get_instruction =
        <list>
                <t>AVAILABLE_ENGINES
                </t>
                <t>/ AVAILABLE_MIDI_INPUT_DRIVERS
                </t>
                <t>/ MIDI_INPUT_DRIVER SP INFO SP string
                </t>
                <t>/ MIDI_INPUT_DRIVER_PARAMETER SP INFO SP string SP string
                </t>
                <t>/ MIDI_INPUT_DRIVER_PARAMETER SP INFO SP string SP string SP key_val_list
                </t>
                <t>/ AVAILABLE_AUDIO_OUTPUT_DRIVERS
                </t>
                <t>/ AUDIO_OUTPUT_DRIVER SP INFO SP string
                </t>
                <t>/ AUDIO_OUTPUT_DRIVER_PARAMETER SP INFO SP string SP string
                </t>
                <t>/ AUDIO_OUTPUT_DRIVER_PARAMETER SP INFO SP string SP string SP key_val_list
                </t>
                <t>/ AUDIO_OUTPUT_DEVICES
                </t>
                <t>/ MIDI_INPUT_DEVICES
                </t>
                <t>/ AUDIO_OUTPUT_DEVICE SP INFO SP number
                </t>
                <t>/ MIDI_INPUT_DEVICE SP INFO SP number
                </t>
                <t>/ MIDI_INPUT_PORT SP INFO SP number SP number
                </t>
                <t>/ MIDI_INPUT_PORT_PARAMETER SP INFO SP number SP number SP string
                </t>
                <t>/ AUDIO_OUTPUT_CHANNEL SP INFO SP number SP number
                </t>
                <t>/ AUDIO_OUTPUT_CHANNEL_PARAMETER SP INFO SP number SP number SP string
                </t>
                <t>/ CHANNELS
                </t>
                <t>/ CHANNEL SP INFO SP sampler_channel
                </t>
                <t>/ CHANNEL SP BUFFER_FILL SP buffer_size_type SP sampler_channel
                </t>
                <t>/ CHANNEL SP STREAM_COUNT SP sampler_channel
                </t>
                <t>/ CHANNEL SP VOICE_COUNT SP sampler_channel
                </t>
                <t>/ ENGINE SP INFO SP engine_name
                </t>
                <t>/ SERVER SP INFO
                </t>
                <t>/ TOTAL_VOICE_COUNT
                </t>
                <t>/ TOTAL_VOICE_COUNT_MAX
                </t>
                <t>/ MIDI_INSTRUMENTS
                </t>
                <t>/ MIDI_INSTRUMENT SP INFO SP midi_bank_msb SP midi_bank_lsb SP midi_prog
                </t>
        </list>
</t>
<t>set_instruction =
        <list>
                <t>AUDIO_OUTPUT_DEVICE_PARAMETER SP number SP string '=' param_val_list
                </t>
                <t>/ AUDIO_OUTPUT_CHANNEL_PARAMETER SP number SP number SP string '=' param_val_list
                </t>
                <t>/ MIDI_INPUT_DEVICE_PARAMETER SP number SP string '=' param_val_list
                </t>
                <t>/ MIDI_INPUT_PORT_PARAMETER SP number SP number SP string '=' param_val_list
                </t>
                <t>/ CHANNEL SP set_chan_instruction
                </t>
                <t>/ ECHO SP boolean
                </t>
        </list>
</t>
<t>create_instruction =
        <list>
                <t>AUDIO_OUTPUT_DEVICE SP string SP key_val_list
                </t>
                <t>/ AUDIO_OUTPUT_DEVICE SP string
                </t>
                <t>/ MIDI_INPUT_DEVICE SP string SP key_val_list
                </t>
                <t>/ MIDI_INPUT_DEVICE SP string
                </t>
        </list>
</t>
<t>reset_instruction =
        <list>
                <t>CHANNEL SP sampler_channel
                </t>
        </list>
</t>
<t>clear_instruction =
        <list>
                <t>MIDI_INSTRUMENTS
                </t>
        </list>
</t>
<t>destroy_instruction =
        <list>
                <t>AUDIO_OUTPUT_DEVICE SP number
                </t>
                <t>/ MIDI_INPUT_DEVICE SP number
                </t>
        </list>
</t>
<t>load_instruction =
        <list>
                <t>INSTRUMENT SP load_instr_args
                </t>
                <t>/ ENGINE SP load_engine_args
                </t>
        </list>
</t>
<t>set_chan_instruction =
        <list>
                <t>AUDIO_OUTPUT_DEVICE SP sampler_channel SP device_index
                </t>
                <t>/ AUDIO_OUTPUT_CHANNEL SP sampler_channel SP audio_channel_index SP audio_channel_index
                </t>
                <t>/ AUDIO_OUTPUT_TYPE SP sampler_channel SP audio_output_type_name
                </t>
                <t>/ MIDI_INPUT SP sampler_channel SP device_index SP midi_input_port_index SP midi_input_channel_index
                </t>
                <t>/ MIDI_INPUT_DEVICE SP sampler_channel SP device_index
                </t>
                <t>/ MIDI_INPUT_PORT SP sampler_channel SP midi_input_port_index
                </t>
                <t>/ MIDI_INPUT_CHANNEL SP sampler_channel SP midi_input_channel_index
                </t>
                <t>/ MIDI_INPUT_TYPE SP sampler_channel SP midi_input_type_name
                </t>
                <t>/ VOLUME SP sampler_channel SP volume_value
                </t>
                <t>/ MUTE SP sampler_channel SP boolean
                </t>
                <t>/ SOLO SP sampler_channel SP boolean
                </t>
        </list>
</t>
<t>key_val_list =
        <list>
                <t>string '=' param_val_list
                </t>
                <t>/ key_val_list SP string '=' param_val_list
                </t>
        </list>
</t>
<t>buffer_size_type =
        <list>
                <t>BYTES
                </t>
                <t>/ PERCENTAGE
                </t>
        </list>
</t>
<t>list_instruction =
        <list>
                <t>AUDIO_OUTPUT_DEVICES
                </t>
                <t>/ MIDI_INPUT_DEVICES
                </t>
                <t>/ CHANNELS
                </t>
                <t>/ AVAILABLE_ENGINES
                </t>
                <t>/ AVAILABLE_MIDI_INPUT_DRIVERS
                </t>
                <t>/ AVAILABLE_AUDIO_OUTPUT_DRIVERS
                </t>
                <t>/ MIDI_INSTRUMENTS
                </t>
        </list>
</t>
<t>load_instr_args =
        <list>
                <t>filename SP instrument_index SP sampler_channel
                </t>
                <t>/ NON_MODAL SP filename SP instrument_index SP sampler_channel
                </t>
        </list>
</t>
<t>load_engine_args =
        <list>
                <t>engine_name SP sampler_channel
                </t>
        </list>
</t>
<t>instr_load_mode =
        <list>
                <t>ON_DEMAND
                </t>
                <t>/ ON_DEMAND_HOLD
                </t>
                <t>/ PERSISTENT
                </t>
        </list>
</t>
<t>device_index =
        <list>
                <t>number
                </t>
        </list>
</t>
<t>audio_channel_index =
        <list>
                <t>number
                </t>
        </list>
</t>
<t>audio_output_type_name =
        <list>
                <t>string
                </t>
        </list>
</t>
<t>midi_input_port_index =
        <list>
                <t>number
                </t>
        </list>
</t>
<t>midi_input_channel_index =
        <list>
                <t>number
                </t>
                <t>/ ALL
                </t>
        </list>
</t>
<t>midi_input_type_name =
        <list>
                <t>string
                </t>
        </list>
</t>
<t>midi_bank_msb =
        <list>
                <t>number
                </t>
        </list>
</t>
<t>midi_bank_lsb =
        <list>
                <t>number
                </t>
        </list>
</t>
<t>midi_prog =
        <list>
                <t>number
                </t>
        </list>
</t>
<t>volume_value =
        <list>
                <t>dotnum
                </t>
                <t>/ number
                </t>
        </list>
</t>
<t>sampler_channel =
        <list>
                <t>number
                </t>
        </list>
</t>
<t>instrument_index =
        <list>
                <t>number
                </t>
        </list>
</t>
<t>engine_name =
        <list>
                <t>string
                </t>
        </list>
</t>
<t>filename =
        <list>
                <t>stringval
                </t>
        </list>
</t>
<t>entry_name =
        <list>
                <t>stringval
                </t>
        </list>
</t>
<t>param_val_list =
        <list>
                <t>param_val
                </t>
                <t>/ param_val_list','param_val
                </t>
        </list>
</t>
<t>param_val =
        <list>
                <t>string
                </t>
                <t>/ stringval
                </t>
                <t>/ number
                </t>
                <t>/ dotnum
                </t>
        </list>
</t>

            <!-- GRAMMAR_BNF_END - do NOT delete or modify this line !!! -->
        </section>

        <section title="Events" anchor="events">
            <t>This chapter will describe all currently defined events supported by LinuxSampler.</t>

            <section title="Number of sampler channels changed" anchor="SUBSCRIBE CHANNEL">
                <t>Client may want to be notified when the total number of channels on the
                back-end changes by issuing the following command:</t>
                <t>
                    <list>
                        <t>SUBSCRIBE CHANNEL_COUNT</t>
                    </list>
                </t>
                <t>Server will start sending the following notification messages:</t>
                <t>
                    <list>
                        <t>"NOTIFY:CHANNEL_COUNT:&lt;channels&gt;"</t>
                    </list>
                </t>
                <t>where &lt;channels&gt; will be replaced by the new number
                of sampler channels.</t>
            </section>

            <section title="Number of active voices changed" anchor="SUBSCRIBE VOICE_COUNT">
                <t>Client may want to be notified when the number of voices on the
                back-end changes by issuing the following command:</t>
                <t>
                    <list>
                        <t>SUBSCRIBE VOICE_COUNT</t>
                    </list>
                </t>
                <t>Server will start sending the following notification messages:</t>
                <t>
                    <list>
                        <t>"NOTIFY:VOICE_COUNT:&lt;sampler-channel&gt; &lt;voices&gt;</t>
                    </list>
                </t>
                <t>where &lt;sampler-channel&gt; will be replaced by the sampler channel the
                voice count change occurred and &lt;voices&gt; by the new number of
                active voices on that channel.</t>
            </section>

            <section title="Number of active disk streams changed" anchor="SUBSCRIBE STREAM_COUNT">
                <t>Client may want to be notified when the number of streams on the back-end
                changes by issuing the following command: SUBSCRIBE STREAM_COUNT</t>
                <t>
                    <list>
                        <t>SUBSCRIBE STREAM_COUNT</t>
                    </list>
                </t>
                <t>Server will start sending the following notification messages:</t>
                <t>
                    <list>
                        <t>"NOTIFY:STREAM_COUNT:&lt;sampler-channel&gt; &lt;streams&gt;"</t>
                    </list>
                </t>
                <t>where &lt;sampler-channel&gt; will be replaced by the sampler channel the
                stream count change occurred and &lt;streams&gt; by the new number of
                active disk streams on that channel.</t>
            </section>

            <section title="Disk stream buffer fill state changed" anchor="SUBSCRIBE BUFFER_FILL">
                <t>Client may want to be notified when the buffer fill state of a disk stream
                on the back-end changes by issuing the following command:</t>
                <t>
                    <list>
                        <t>SUBSCRIBE BUFFER_FILL</t>
                    </list>
                </t>
                <t>Server will start sending the following notification messages:</t>
                <t>
                    <list>
                        <t>"NOTIFY:BUFFER_FILL:&lt;sampler-channel&gt; &lt;fill-data&gt;"</t>
                    </list>
                </t>
                <t>where &lt;sampler-channel&gt; will be replaced by the sampler channel the
                buffer fill state change occurred on and &lt;fill-data&gt; will be replaced by the
                buffer fill data for this channel as described in <xref target="GET CHANNEL BUFFER_FILL" />
                as if the <xref target="GET CHANNEL BUFFER_FILL">
                "GET CHANNEL BUFFER_FILL PERCENTAGE"</xref> command was issued on this channel.</t>
            </section>

            <section title="Channel information changed" anchor="SUBSCRIBE INFO">
                <t>Client may want to be notified when changes were made to sampler channels on the
                back-end by issuing the following command:</t>
                <t>
                    <list>
                        <t>SUBSCRIBE CHANNEL_INFO</t>
                    </list>
                </t>
                <t>Server will start sending the following notification messages:</t>
                <t>
                    <list>
                        <t>"NOTIFY:CHANNEL_INFO:&lt;sampler-channel&gt;"</t>
                    </list>
                </t>
                <t>where &lt;sampler-channel&gt; will be replaced by the sampler channel the
                channel info change occurred. The front-end will have to send
                the respective command to actually get the channel info. Because these messages
                will be triggered by LSCP commands issued by other clients rather than real
                time events happening on the server, it is believed that an empty notification
                message is sufficient here.</t>
            </section>

            <section title="Total number of active voices changed" anchor="SUBSCRIBE TOTAL_VOICE_COUNT">
                <t>Client may want to be notified when the total number of voices on the
                back-end changes by issuing the following command:</t>
                <t>
                    <list>
                        <t>SUBSCRIBE TOTAL_VOICE_COUNT</t>
                    </list>
                </t>
                <t>Server will start sending the following notification messages:</t>
                <t>
                    <list>
                        <t>"NOTIFY:TOTAL_VOICE_COUNT:&lt;voices&gt;</t>
                    </list>
                </t>
                <t>where &lt;voices&gt; will be replaced by the new number of
                all currently active voices.</t>
            </section>

            <section title="Miscellaneous and debugging events" anchor="SUBSCRIBE MISCELLANEOUS">
                <t>Client may want to be notified of miscellaneous and debugging events occurring at
                the server by issuing the following command:</t>
                <t>
                    <list>
                        <t>SUBSCRIBE MISCELLANEOUS</t>
                    </list>
                </t>
                <t>Server will start sending the following notification messages:</t>
                <t>
                    <list>
                        <t>"NOTIFY:MISCELLANEOUS:&lt;string&gt;"</t>
                    </list>
                </t>
                <t>where &lt;string&gt; will be replaced by whatever data server
                wants to send to the client. Client MAY display this data to the
                user AS IS to facilitate debugging.</t>
            </section>
        </section>

        <section title="Security Considerations">
            <t>As there is so far no method of authentication and authorization
            defined and so not required for a client applications to succeed to
            connect, running LinuxSampler might be a security risk for the host
            system the LinuxSampler instance is running on.</t>
        </section>

        <section title="Acknowledgments">
            <t>This document has benefited greatly from the comments of the
            following people, discussed on the LinuxSampler developer's mailing
            list:</t>
            <t>
                <list>
                    <t>Rui Nuno Capela</t>
                    <t>Vladimir Senkov</t>
                    <t>Mark Knecht</t>
                    <t>Grigor Iliev</t>
                </list>
            </t>
        </section>

    </middle>

    <back>
        <references>
            <reference anchor="RFC2119">
                <front>
                    <title>Key words for use in RFCs to Indicate Requirement Levels</title>
                    <author initials="S." surname="Bradner" fullname="Scott Bradner">
                        <organization>Harvard University</organization>
                    </author>
                    <date year="1997"></date>
                </front>
                <seriesInfo name="RFC" value="2119" />
            </reference>
            <reference anchor="RFC793">
                <front>
                    <title>TRANSMISSION CONTROL PROTOCOL</title>
                    <author>
                        <organization>Defense Advanced Research Projects Agency</organization>
                    </author>
                    <date year="1981"></date>
                </front>
                <seriesInfo name="RFC" value="793" />
            </reference>
            <reference anchor="RFC2234">
                <front>
                    <title>Augmented BNF for Syntax Specifications</title>
                    <author initials="D.H." surname="Crocker" fullname="David H. Crocker">
                        <organization>Internet Mail Consortium</organization>
                    </author>
                    <author initials="P." surname="Overell" fullname="Paul Overell">
                        <organization>Demon Internet Ltd</organization>
                    </author>
                    <date year="1997"></date>
                </front>
                <seriesInfo name="RFC" value="2234" />
            </reference>
         </references>
    </back>

</rfc>