Create a stacked channel with the given mode (i.e. readable/writable) and which is implemented using the given ensemble-like command (or command prefix; it may include multiple words).

'''chan create''' ''mode cmdPrefix''

If ''cmdPrefix'' is "foo bar" (no quotes) and the mode is "read" then the call to initialize the channel (done during '''chan create''') will be:

 foo bar initialize <thechanname> read

[[ To do: document the API expected to be used by the implementation command ]]

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'''Required Subcommands'''

''cmdPrefix'' '''initialize''' ''channelId mode''
- Must be supported. Must return list of all subcommands supported (i.e., minimally '''initialize''', '''finalize''' and '''watch''').

''cmdPrefix'' '''finalize''' ''channelId''
- Must be supported. Must not access the channel in any way.

''cmdPrefix'' '''watch''' ''channelId eventSpec''
- Must be supported. Interacts with [chan postevent].

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'''Optional Subcommands'''

''cmdPrefix'' '''read''' ''channelId count''
- Non-readable channels do not need this command.

''cmdPrefix'' '''write''' ''channelId data''
- Non-writable channels do not need this command.

''cmdPrefix'' '''seek''' ''channelId offset base''
- Non-seekable channels do not need this command. Both [chan seek] and [chan tell] use this.

''cmdPrefix'' '''configure''' ''channelId option value''

''cmdPrefix'' '''cget''' ''channelId option''
- If supported, the '''cgetall''' subcommand must also be supported.

''cmdPrefix'' '''cgetall''' ''channelId''
- If supported, the '''cget''' subcommand must also be supported.

''cmdPrefix'' '''blocking''' ''channelId mode''

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[[[Category Command]]]