bool al_save_bitmap_f(ALLEGRO_FILE *fp, const char *ident,
Saves an ALLEGRO_BITMAP(3alleg5) to an ALLEGRO_FILE(3alleg5) stream. The file type is determined by the passed 'ident' parameter, which is a file name extension including the leading dot.
Returns true on success, false on error. The file remains open afterwards.
Note: the core Allegro library does not support any image file formats by default. You must use the allegro_image addon, or register your own format handler.