int load_ibk(char *filename, int drums);
Reads in a .IBK patch definition file for use by the Adlib driver. If drums is set, it will load it as a percussion patch set, otherwise it will use it as a replacement set of General MIDI instruments. You may call this before or after initialising the sound code, or can simply set the ibk_file and ibk_drum_file variables in the configuration file to have the data loaded automatically. Note that this function has no effect on any drivers other than the Adlib one!
Returns non-zero on error.