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''

[[ 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]]]