man get_mixer_channels () - Returns the number of output channels. Allegro game programming library.
NAME
get_mixer_channels - Returns the number of output channels. Allegro game programming library.
SYNOPSIS
#include <allegro.h>
int get_mixer_channels(void);
DESCRIPTION
Returns the number of output channels. 2 for stereo, 1 for mono, 0 if the mixer isn't active.