al_identify_sample_f - Allegro 5 API

       Tries  to  guess the audio file type of the open ALLEGRO_FILE by reading the first few bytes.  By default
       Allegro cannot recognize any file types, but calling al_init_acodec_addon(3alleg5) will add detection  of
       the types it can read.  You can also use al_register_sample_identifier(3alleg5) to add identification for
       custom file types.

       Returns  a pointer to a static string with a file extension for the type, including the leading dot.  For
       example “.wav” or “.ogg”.  Returns NULL if the audio type cannot be determined.

       al_identify_sample_f - Allegro 5 API

al_init_acodec_addon(3alleg5), al_identify_sample(3alleg5), al_register_sample_identifier(3alleg5)

Allegro reference manual                                                           al_identify_sample_f(3alleg5)

       5.2.8

              #include <allegro5/allegro_audio.h>

              char const *al_identify_sample_f(ALLEGRO_FILE *fp)