The argument is a tab representing a midi message, see function @midi_read. The @midi_getChannel extracts from this tab the channel of the message if the message corresponds to a channel specific command (i.e., noteOn, noteOff, Aftertouch, Controller, PatchChange, Pressure and Pitchbend, see @midi_read).

On a non-channel specific command, the result is undeterminate.

See also Handling Midi @hz2midi    @hz2midicent    @hz2symb    @midi_getChannel,    @midi_getCommandByte,    @midi_getCommand,    @midi_getMetaType,    @midi_isAftertouch,    @midi_isController,    @midi_isEndOfTrack,    @midi_isMeta,    @midi_isNoteOff,    @midi_isNoteOn,    @midi_isNote,    @midi_isPatchChange,    @midi_isPitchbend,    @midi_isPressure,    @midi_isTempo,    @midi_read,    @midi_track2ascii    @midi2hz    @midicent2hz    @symb2midicent