[MPlayer-users] Selecting the audio device in OS/X

[Reimar Döffinger]

On Thu, Feb 09, 2012 at 06:13:00PM +0000, Zak Mc Kracken wrote:
> Anyway, I had already tried many variants one could think of, like
> coreaudio:help, coreaudio:device_id=help coreaudio:device_id=list
> coreaudio:list.

Hm, it is supposed to print the device list whenever it can't parse the
option.

> And yes, adding the mandatory file parameter (by the
> way, the command line parser should not require that when I'm just
> passing the help/list option; if it does it, I think it's a minor
> bug).

The reason is not so simple: Those are options for the audio output,
and can (and in this case are) dynamically generated after the audio
output has been initialized.
Initializing an audio output when the user does not want any audio
can be problematic.
Overall this leads to the fact that if there is no audio to play,
MPlayer will not give you help on any audio output options.