allegro_error (3alleg4)

#include <allegro.h>

extern char allegro_error[ALLEGRO_ERROR_SIZE];

Text string used by set_gfx_mode(), install_sound() and other functions to report error messages. If they fail and you want to tell the user why, this is the place to look for a description of the problem. Example:

   void abort_on_error(const char *message)
   {
      if (screen != NULL)
         set_gfx_mode(GFX_TEXT, 0, 0, 0, 0);

      allegro_message("%s.\nLast Allegro error `%s'\n",
                      message, allegro_error);
      exit(-1);
   }
   ...
      if (some_allegro_function() == ERROR_CODE)
         abort_on_error("Error calling some function!");

set_gfx_mode(3alleg4), install_sound(3alleg4)