AL_ID - Man Page

#include <allegro.h>

Macro AL_ID(a,b,c,d)

This macro can be used to create a packed 32 bit integer from 8 bit characters, on both 32 and 64 bit machines. These can be used for various  things, like custom datafile objects or system IDs. Example:

   #define OSTYPE_LINUX       AL_ID('T','U','X',' ')

DAT_ID(3)