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al_fixsub(3)							  al_fixsub(3)

NAME
       al_fixsub - Allegro 5 API

SYNOPSIS
	      #include <allegro5/allegro.h>

	      al_fixed al_fixsub(al_fixed x, al_fixed y);

DESCRIPTION
       Although	 fixed point numbers can be subtracted with the	normal - inte-
       ger operator, that doesn't provide any protection against overflow.  If
       overflow	 is  a	problem,  you should use this function instead.	 It is
       slower than using integer operators, but	if an overflow occurs it  will
       set  Allegro's  errno and clamp the result, rather than just letting it
       wrap.

       Example:

		  al_fixed result;

		  /* This will put 4965	into `result'. */
		  result = al_fixsub(al_itofix(5000), al_itofix(35));

		  /* Sets errno	and puts -32768	into `result'. */
		  result = al_fixsub(al_itofix(-31000),	al_itofix(3000));
		  assert(!al_get_errno()); /* This will	fail. */

RETURN VALUE
       Returns the clamped result of subtracting y from	x,  setting  Allegro's
       errno to	ERANGE if there	was an overflow.

SEE ALSO
       al_fixadd(3), al_fixmul(3), al_fixdiv(3), al_get_errno(3).

Allegro	reference manual					  al_fixsub(3)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | SEE ALSO

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