allegro_404_char - Character used when Allegro cannot find a glyph.

       When  Allegro  cannot  find  a  glyph  it  needs in a font, it will instead output the character given in
       allegro_404_char. By default, this is set to the caret symbol, `^', but you can change this global to use
       any other character instead. Example:

          /* Show unknown glyphs with an asterisk. */
          allegro_404_char = '*';

       allegro_404_char - Character used when Allegro cannot find a glyph.

font(3alleg4)

Allegro                                           version 4.4.3                        allegro_404_char(3alleg4)

#include<allegro.h>externintallegro_404_char;