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|
<?xml version="1.0" ?>
<node name="/Channel_Type_Text" xmlns:tp="http://telepathy.freedesktop.org/wiki/DbusSpec#extensions-v0">
<tp:copyright> Copyright © 2005-2009 Collabora Limited </tp:copyright>
<tp:copyright> Copyright © 2005-2009 Nokia Corporation </tp:copyright>
<tp:copyright> Copyright © 2006 INdT </tp:copyright>
<tp:license xmlns="http://www.w3.org/1999/xhtml">
<p>This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.</p>
<p>This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.</p>
<p>You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.</p>
</tp:license>
<interface name="org.freedesktop.Telepathy.Channel.Type.Text">
<tp:requires interface="org.freedesktop.Telepathy.Channel"/>
<tp:requires
interface="org.freedesktop.Telepathy.Channel.Interface.Messages"/>
<tp:changed version="0.21.5">The Messages interface is now
mandatory</tp:changed>
<tp:changed version="0.24.0">This interface used to have a bunch of
clunky <tp:dbus-ref
namespace='org.freedesktop'>Telepathy.Properties</tp:dbus-ref>. They have
been removed in favour of D-Bus properties on the <tp:dbus-ref
namespace='ofdT.Channel.Interface'>Room2</tp:dbus-ref>, <tp:dbus-ref
namespace='ofdT.Channel.Interface'>Subject2</tp:dbus-ref> and
<tp:dbus-ref namespace='ofdT.Channel.Interface'>RoomConfig1</tp:dbus-ref>
interfaces.</tp:changed>
<tp:simple-type name="Message_ID" type="u" array-name="Message_ID_List">
<tp:docstring>
A unique-per-channel identifier for an incoming message. These
SHOULD be allocated in a way that minimizes collisions (in particular,
message IDs SHOULD NOT be re-used until all of the 32-bit integer
space has already been used).
</tp:docstring>
</tp:simple-type>
<tp:struct name="Pending_Text_Message" array-name="Pending_Text_Message_List">
<tp:deprecated version="0.21.5">New APIs should use
an array of <tp:type>Message_Part</tp:type> instead.</tp:deprecated>
<tp:docstring>A struct (message ID, timestamp in seconds since
1970-01-01 00:00 UTC, sender's handle, message type, flags, text)
representing a pending text message, as returned by
<tp:member-ref>ListPendingMessages</tp:member-ref>. The arguments of
the <tp:member-ref>Received</tp:member-ref> signal also match this
struct's signature.</tp:docstring>
<tp:member type="u" tp:type="Message_ID" name="Identifier"/>
<tp:member type="u" tp:type="Unix_Timestamp" name="Unix_Timestamp"/>
<tp:member type="u" tp:type="Contact_Handle" name="Sender"/>
<tp:member type="u" tp:type="Channel_Text_Message_Type"
name="Message_Type"/>
<tp:member type="u" tp:type="Channel_Text_Message_Flags" name="Flags"/>
<tp:member type="s" name="Text"/>
</tp:struct>
<method name="AcknowledgePendingMessages"
tp:name-for-bindings="Acknowledge_Pending_Messages">
<arg direction="in" name="IDs" type="au" tp:type="Message_ID[]">
<tp:docstring>
The IDs of the messages to acknowledge
</tp:docstring>
</arg>
<tp:docstring>
Inform the channel that you have handled messages by displaying them to
the user (or equivalent), so they can be removed from the pending queue.
</tp:docstring>
<tp:possible-errors>
<tp:error name="org.freedesktop.Telepathy.Error.InvalidArgument">
<tp:docstring>
A given message ID was not found, so no action was taken
</tp:docstring>
</tp:error>
</tp:possible-errors>
</method>
<method name="GetMessageTypes" tp:name-for-bindings="Get_Message_Types">
<tp:deprecated version="0.21.5">Consulting
<tp:dbus-ref namespace="ofdT.Channel.Interface.Messages"
>MessageTypes</tp:dbus-ref> is preferred.
</tp:deprecated>
<arg direction="out" type="au" tp:type="Channel_Text_Message_Type[]"
name="Available_Types">
<tp:docstring>
An array of integer message types (ChannelTextMessageType)
</tp:docstring>
</arg>
<tp:docstring>
Return an array indicating which types of message may be sent on this
channel.
</tp:docstring>
</method>
<method name="ListPendingMessages"
tp:name-for-bindings="List_Pending_Messages">
<tp:deprecated version="0.21.5">Consulting
<tp:dbus-ref namespace="ofdT.Channel.Interface.Messages"
>PendingMessages</tp:dbus-ref> is preferred.
</tp:deprecated>
<arg direction="in" name="Clear" type="b">
<tp:docstring>
If true, behave as if
<tp:member-ref>AcknowledgePendingMessages</tp:member-ref> had also
been called.
</tp:docstring>
<tp:deprecated version="0.17.3">
Setting this to true is NOT RECOMMENDED for clients that
have some sort of persistent message storage - clients SHOULD only
acknowledge messages after they have actually stored them, which is
impossible if this flag is true.</tp:deprecated>
</arg>
<arg direction="out" type="a(uuuuus)" tp:type="Pending_Text_Message[]"
name="Pending_Messages">
<tp:docstring xmlns="http://www.w3.org/1999/xhtml">
An array of structs representing the pending queue. Each contains:
<ul>
<li>a numeric identifier</li>
<li>a Unix timestamp indicating when the message was received</li>
<li>the contact handle for the contact who sent the message</li>
<li>the message type, taken from ChannelTextMessageType</li>
<li>the bitwise-OR of the message flags from ChannelTextMessageFlags</li>
<li>the text of the message</li>
</ul>
</tp:docstring>
</arg>
<tp:docstring>
List the messages currently in the pending queue, and optionally
remove then all.
</tp:docstring>
</method>
<signal name="LostMessage" tp:name-for-bindings="Lost_Message">
<tp:deprecated version="0.21.5">In practice, this signal
was not emitted, and does not have useful semantics.</tp:deprecated>
<tp:docstring>
This signal is emitted to indicate that an incoming message was
not able to be stored and forwarded by the connection manager
due to lack of memory.
</tp:docstring>
</signal>
<signal name="Received" tp:name-for-bindings="Received">
<tp:deprecated version="0.21.5">The
<tp:dbus-ref namespace="ofdT.Channel.Interface.Messages"
>MessageReceived</tp:dbus-ref> signal is more informative.
</tp:deprecated>
<arg name="ID" type="u">
<tp:docstring>
A numeric identifier for acknowledging the message
</tp:docstring>
</arg>
<arg name="Timestamp" type="u" tp:type="Unix_Timestamp">
<tp:docstring>
A Unix timestamp indicating when the message was received
</tp:docstring>
</arg>
<arg name="Sender" type="u" tp:type="Contact_Handle">
<tp:docstring>
The handle of the contact who sent the message
</tp:docstring>
</arg>
<arg name="Type" type="u" tp:type="Channel_Text_Message_Type">
<tp:docstring>
The type of the message (normal, action, notice, etc.)
</tp:docstring>
</arg>
<arg name="Flags" type="u" tp:type="Channel_Text_Message_Flags">
<tp:docstring>
A bitwise OR of the message flags
</tp:docstring>
</arg>
<arg name="Text" type="s">
<tp:docstring>
The text of the message
</tp:docstring>
</arg>
<tp:docstring>
Signals that a message with the given id, timestamp, sender, type
and text has been received on this channel. Applications that catch
this signal and reliably inform the user of the message should
acknowledge that they have dealt with the message with the
<tp:member-ref>AcknowledgePendingMessages</tp:member-ref> method.
</tp:docstring>
</signal>
<method name="Send" tp:name-for-bindings="Send">
<tp:deprecated version="0.21.5">The
<tp:dbus-ref namespace="ofdT.Channel.Interface.Messages"
>SendMessage</tp:dbus-ref> method is more flexible.
</tp:deprecated>
<arg direction="in" name="Type" type="u" tp:type="Channel_Text_Message_Type">
<tp:docstring>
An integer indicating the type of the message
</tp:docstring>
</arg>
<arg direction="in" name="Text" type="s">
<tp:docstring>
The message to send
</tp:docstring>
</arg>
<tp:docstring xmlns="http://www.w3.org/1999/xhtml">
<p>Request that a message be sent on this channel. When the message has
been submitted for delivery, this method will return and the
<tp:member-ref>Sent</tp:member-ref> signal will be emitted. If the
message cannot be submitted for delivery, the method returns an error
and no signal is emitted.</p>
<p>This method SHOULD return before the Sent signal is
emitted.</p>
<tp:rationale>
<p>When a Text channel implements the <tp:dbus-ref
namespace="org.freedesktop.Telepathy.Channel.Interface">Messages</tp:dbus-ref>
interface, that "SHOULD" becomes a "MUST".</p>
</tp:rationale>
</tp:docstring>
<tp:possible-errors>
<tp:error name="org.freedesktop.Telepathy.Error.Disconnected"/>
<tp:error name="org.freedesktop.Telepathy.Error.NetworkError"/>
<tp:error name="org.freedesktop.Telepathy.Error.InvalidArgument"/>
<tp:error name="org.freedesktop.Telepathy.Error.PermissionDenied"/>
</tp:possible-errors>
</method>
<tp:enum name="Channel_Text_Send_Error" type="u">
<tp:enumvalue suffix="Unknown" value="0">
<tp:docstring>
An unknown error occurred
</tp:docstring>
</tp:enumvalue>
<tp:enumvalue suffix="Offline" value="1">
<tp:docstring>
The requested contact was offline
</tp:docstring>
</tp:enumvalue>
<tp:enumvalue suffix="Invalid_Contact" value="2">
<tp:docstring>
The requested contact is not valid
</tp:docstring>
</tp:enumvalue>
<tp:enumvalue suffix="Permission_Denied" value="3">
<tp:docstring>
The user does not have permission to speak on this channel
</tp:docstring>
</tp:enumvalue>
<tp:enumvalue suffix="Too_Long" value="4">
<tp:docstring>
The outgoing message was too long and was rejected by the server
</tp:docstring>
</tp:enumvalue>
<tp:enumvalue suffix="Not_Implemented" value="5">
<tp:docstring>
The channel doesn't support sending text messages to the requested
contact
</tp:docstring>
</tp:enumvalue>
</tp:enum>
<signal name="SendError" tp:name-for-bindings="Send_Error">
<tp:deprecated version="0.21.5">Delivery reporting is now
provided by the <tp:dbus-ref namespace="ofdT.Channel.Interface"
>Messages</tp:dbus-ref> interface.
</tp:deprecated>
<arg name="Error" type="u" tp:type="Channel_Text_Send_Error">
<tp:docstring>
The error that occurred
</tp:docstring>
</arg>
<arg name="Timestamp" type="u" tp:type="Unix_Timestamp">
<tp:docstring>
The Unix timestamp indicating when the message was sent
</tp:docstring>
</arg>
<arg name="Type" type="u" tp:type="Channel_Text_Message_Type">
<tp:docstring>
The message type
</tp:docstring>
</arg>
<arg name="Text" type="s">
<tp:docstring>
The text of the message
</tp:docstring>
</arg>
<tp:docstring xmlns="http://www.w3.org/1999/xhtml">
<p>Signals that an outgoing message has failed to send. The error
will be one of the values from ChannelTextSendError.</p>
<p>This signal should only be emitted for messages for which
<tp:member-ref>Sent</tp:member-ref> has already been emitted and
<tp:member-ref>Send</tp:member-ref> has already returned success.</p>
</tp:docstring>
<tp:changed version="0.17.3">older spec versions claimed that SendError
was emitted <em>instead of</em> Sent, rather than <em>in addition
to</em> Sent. However, the 0.17.3+ semantics were what we'd always
actually implemented.</tp:changed>
</signal>
<signal name="Sent" tp:name-for-bindings="Sent">
<tp:deprecated version="0.21.5">The
<tp:dbus-ref namespace="ofdT.Channel.Interface.Messages"
>MessageSent</tp:dbus-ref> signal is more informative.
</tp:deprecated>
<arg name="Timestamp" type="u" tp:type="Unix_Timestamp">
<tp:docstring>
Unix timestamp indicating when the message was sent
</tp:docstring>
</arg>
<arg name="Type" type="u" tp:type="Channel_Text_Message_Type">
<tp:docstring>
The message type (normal, action, notice, etc) from
ChannelTextMessageType
</tp:docstring>
</arg>
<arg name="Text" type="s">
<tp:docstring>
The text of the message. If the message was, or will be, altered
during transmission, this argument SHOULD reflect what other
contacts will receive rather than being a copy of the argument
to <tp:member-ref>Send</tp:member-ref>.
</tp:docstring>
</arg>
<tp:docstring xmlns="http://www.w3.org/1999/xhtml">
<p>Signals that a message has been submitted for sending.</p>
</tp:docstring>
</signal>
<tp:enum name="Channel_Text_Message_Type" type="u"
array-name="Channel_Text_Message_Type_List">
<tp:docstring>
The type of message.
</tp:docstring>
<tp:enumvalue suffix="Normal" value="0">
<tp:docstring>
An ordinary chat message. Unknown types SHOULD be treated like this.
</tp:docstring>
</tp:enumvalue>
<tp:enumvalue suffix="Action" value="1">
<tp:docstring>
An action which might be presented to the user as
"* <sender> <action>", such as an IRC CTCP
ACTION (typically selected by the "/me" command). For example, the
text of the message might be "drinks more coffee".
</tp:docstring>
</tp:enumvalue>
<tp:enumvalue suffix="Notice" value="2">
<tp:docstring>
A one-off or automated message not necessarily expecting a reply
</tp:docstring>
</tp:enumvalue>
<tp:enumvalue suffix="Auto_Reply" value="3">
<tp:docstring>
An automatically-generated reply message.
</tp:docstring>
</tp:enumvalue>
<tp:enumvalue suffix="Delivery_Report" value="4">
<tp:docstring>
A delivery report. This message type MUST NOT appear unless the
channel supports the <tp:dbus-ref
namespace="org.freedesktop.Telepathy.Channel.Interface">Messages</tp:dbus-ref>
interface; see <tp:type>Message_Part</tp:type> for the format that
delivery reports must take.
</tp:docstring>
</tp:enumvalue>
</tp:enum>
<tp:flags name="Channel_Text_Message_Flags" value-prefix="Channel_Text_Message_Flag" type="u">
<tp:deprecated version="0.21.5">The
<tp:dbus-ref namespace="ofdT.Channel.Interface"
>Messages</tp:dbus-ref> interface has an extensible data structure
including separate booleans for most of these flags.
</tp:deprecated>
<tp:flag suffix="Truncated" value="1">
<tp:docstring>
The incoming message was truncated to a shorter length by the
server or the connection manager.
</tp:docstring>
</tp:flag>
<tp:flag suffix="Non_Text_Content" value="2">
<tp:docstring xmlns="http://www.w3.org/1999/xhtml">
<p>The incoming message contained non-text content which cannot be
represented by this interface, but has been signalled
in the <tp:dbus-ref
namespace="org.freedesktop.Telepathy.Channel.Interface">Messages</tp:dbus-ref>
interface.</p>
<p>Connection managers SHOULD only set this flag if the non-text
content appears to be relatively significant (exactly how
significant is up to the implementor). The intention is that
if this flag is set, clients using this interface SHOULD inform
the user that part of the message was not understood.</p>
</tp:docstring>
</tp:flag>
<tp:flag suffix="Scrollback" value="4">
<tp:docstring xmlns="http://www.w3.org/1999/xhtml">
<p>The incoming message was part of a replay of message history.</p>
<tp:rationale>
<p>In XMPP multi-user chat, a few past messages are replayed
when you join a chatroom. A sufficiently capable IRC connection
manager could also set this flag on historical messages when
connected to a proxy like bip or irssi-proxy. The existence
of this flag allows loggers and UIs to use better heuristics
when eliminating duplicates (a simple implementation made
possible by this flag would be to avoid logging scrollback
at all).</p>
</tp:rationale>
</tp:docstring>
</tp:flag>
<tp:flag suffix="Rescued" value="8">
<tp:docstring xmlns="http://www.w3.org/1999/xhtml">
<p>The incoming message has been seen in a previous channel during
the lifetime of the <tp:dbus-ref
namespace="org.freedesktop.Telepathy">Connection</tp:dbus-ref>, but
had not been acknowledged
when that channel closed, causing an identical channel (the
channel in which the message now appears) to open.</p>
<tp:rationale>
<p>This means that a logger (which should already have seen the
message in the previous channel) is able to recognise and ignore
these replayed messages.</p>
</tp:rationale>
</tp:docstring>
</tp:flag>
</tp:flags>
<tp:docstring xmlns="http://www.w3.org/1999/xhtml">
<p>A channel type for sending and receiving messages. This channel type
is primarily used for textual messages, but can also be used for
formatted text, text with "attachments", or binary messages on some
protocols.</p>
<p>Most of the methods and signals on this interface are deprecated,
since they only support plain-text messages with limited metadata.
See the mandatory <tp:dbus-ref
namespace="ofdT.Channel.Interface">Messages</tp:dbus-ref>
interface for the modern equivalents.</p>
<p>When a message is received, an identifier is assigned and a
<tp:dbus-ref namespace="ofdT.Channel.Interface.Messages"
>MessageReceived</tp:dbus-ref> signal emitted, and the message
is placed in a pending queue represented by the
<tp:dbus-ref namespace="ofdT.Channel.Interface.Messages"
>PendingMessages</tp:dbus-ref> property.
When the <tp:dbus-ref
namespace="org.freedesktop.Telepathy.Client">Handler</tp:dbus-ref>
for a channel has handled the message by showing it to the user
(or equivalent), it should acknowledge the receipt of that message
using the <tp:member-ref>AcknowledgePendingMessages</tp:member-ref>
method, and the message will then be removed from the pending queue.
Numeric identifiers for received messages may be reused over the
lifetime of the channel.</p>
<p>Sending messages can be requested using the
<tp:dbus-ref namespace="ofdT.Channel.Interface.Messages"
>SendMessage</tp:dbus-ref> method, which will return
successfully when the message has been submitted for sending, or
return an error with no signal emission if there is an immediate
failure. If a message is submitted for sending but delivery of the
message later fails, this is indicated by a delivery report, which
is received in the same way as an incoming message.</p>
<p>Simple one-to-one chats (such as streams of private messages in
XMPP or IRC) should be represented by a Text channel whose
<tp:dbus-ref namespace="ofdT.Channel">TargetHandleType</tp:dbus-ref>
is <tp:value-ref type="Handle_Type">Contact</tp:value-ref>. The
expected way to request such a channel is to set the <tp:dbus-ref
namespace='ofdT.Channel'>ChannelType</tp:dbus-ref>, <tp:dbus-ref
namespace='ofdT.Channel'>TargetHandleType</tp:dbus-ref>,
and either <tp:dbus-ref
namespace='ofdT.Channel'>TargetHandle</tp:dbus-ref> or <tp:dbus-ref
namespace='ofdT.Channel'>TargetID</tp:dbus-ref> in a call to
<tp:dbus-ref
namespace='ofdT.ChannelDispatcher'>EnsureChannel</tp:dbus-ref>.</p>
<p>Named chat rooms whose identity can be saved and used again later
(IRC channels, Jabber MUCs) are expected to be represented by Text
channels with <tp:dbus-ref
namespace="ofdT.Channel">TargetHandleType</tp:dbus-ref> =
<tp:value-ref type="Handle_Type">Room</tp:value-ref> and the
<tp:dbus-ref namespace="ofdT.Channel.Interface">Group</tp:dbus-ref>
interface. In protocols where a chatroom can be used as a continuation
of one or more one-to-one chats, these channels should also have the
<tp:dbus-ref namespace="ofdT.Channel.Interface">Conference</tp:dbus-ref>
interface.</p>
<p>Unnamed, transient chat rooms which cannot be rejoined by their
unique identifier (e.g. a conversation on MSN which has, or once had,
three or more participants) are expected to be represented by Text
channels with <tp:dbus-ref
namespace="ofdT.Channel">TargetHandleType</tp:dbus-ref> = <tp:value-ref
type="Handle_Type">None</tp:value-ref> (and hence <tp:dbus-ref
namespace="ofdT.Channel">TargetHandle</tp:dbus-ref> = 0),
<tp:dbus-ref namespace="ofdT.Channel.Interface">Group</tp:dbus-ref>
interface, and optionally the
<tp:dbus-ref namespace="ofdT.Channel.Interface">Conference</tp:dbus-ref>
interface.</p>
<p>On protocols like MSN where a conversation with a user is actually
just a nameless chat room starting with exactly two members, to which
more members can be invited, the initial one-to-one conversation
SHOULD be represented with <tp:dbus-ref
namespace="ofdT.Channel">TargetHandleType</tp:dbus-ref> =
<tp:value-ref type="Handle_Type">Contact</tp:value-ref>. If a third
participant
joins or is invited, this SHOULD be represented by signalling
a new <tp:dbus-ref
namespace="ofdT.Channel.Interface">Conference</tp:dbus-ref> channel
with the one-to-one channel in its <tp:dbus-ref
namespace="ofdT.Channel.Interface.Conference"
>InitialChannels</tp:dbus-ref>, migrating the underlying protocol
object from the one-to-one channel to the Conference channel,
and creating a new protocol-level conversation if the one-to-one
channel is re-used. See the Conference interface for more details.</p>
<tp:rationale>
<p>This keeps the presentation of all one-to-one conversations
uniform, and makes it easier to hand over a conversation from a
1-1-specific UI to a more elaborate multi-user UI; while it does
require UIs to understand Conference to follow the
upgrade, UIs that will deal with XMPP need to understand Conference
anyway.</p>
</tp:rationale>
<p>If a channel of type Text is closed while it has pending messages,
the connection manager MUST allow this, but SHOULD open a new channel
to deliver those messages, signalling it as a new channel with the
<tp:dbus-ref
namespace="ofdT.Connection.Interface.Requests">NewChannels</tp:dbus-ref>
signal. The new channel should resemble the old channel, but have
<tp:dbus-ref namespace='ofdT.Channel'>Requested</tp:dbus-ref> = FALSE
regardless of its previous value; the <tp:dbus-ref
namespace='ofdT.Channel'>InitiatorHandle</tp:dbus-ref>
and <tp:dbus-ref namespace='ofdT.Channel'>InitiatorID</tp:dbus-ref>
should correspond to the sender of one of the pending
messages.</p>
<tp:rationale>
<p>In effect, this turns this situation, in which a client
is likely to lose messages:</p>
<ul>
<li>UI window is closed</li>
<li>message arrives</li>
<li>text channel emits Received</li>
<li>UI calls Close on text channel before it has seen the
Received signal</li>
<li>text channel emits Closed and closes</li>
</ul>
<p>into something nearly equivalent to this situation, which is
fine:</p>
<ul>
<li>UI window is closed</li>
<li>UI calls Close on text channel</li>
<li>text channel emits Closed and closes</li>
<li>message arrives</li>
<li>new text channel is created, connection emits NewChannels</li>
<li>(the same or a different) UI handles it</li>
</ul>
<p>Requested must be set to FALSE so the replacement channel
will be handled by something.</p>
<p>In practice, connection managers usually implement this by keeping
the same internal object that represented the old channel, adjusting
its properties, signalling that it was closed, then immediately
re-signalling it as a new channel.</p>
</tp:rationale>
<p>As a result, Text channels SHOULD implement <tp:dbus-ref
namespace="ofdT">Channel.Interface.Destroyable</tp:dbus-ref>.</p>
<tp:rationale>
<p>This "respawning" behaviour becomes problematic if there is no
suitable handler for Text channels, or if a particular message
repeatedly crashes the Text channel handler; a channel dispatcher
can't just Close() the channel in these situations, because
it will come back.</p>
<p>In these situations, the channel dispatcher needs a last-resort
way to destroy the channel and stop it respawning. It could either
acknowledge the messages itself, or use the Destroyable interface;
the Destroyable interface has the advantage that it's not
channel-type-dependent, so the channel dispatcher only has to
understand one extra interface, however many channel types
eventually need a distinction between Close and Destroy.</p>
</tp:rationale>
<p>Opaquely-named rejoinable chatrooms (such as Skype rooms) are
represented using the properties in the <tp:dbus-ref
namespace="ofdT.Channel.Interface">Room2</tp:dbus-ref>
interface. Instructions and examples of how to request
such channels are given in said interface's description.</p>
</tp:docstring>
</interface>
</node>
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