Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
fixmul(3)			 Allegro manual 		       fixmul(3)

NAME
     fixmul  - Multiplies two fixed point values together. Allegro game program-
     ming library.

SYNOPSIS
     #include <allegro.h>

     fixed fixmul(fixed x, fixed y);

DESCRIPTION
     A fixed point value can be multiplied or divided by  an  integer  with  the
     normal  `*'  and `/' operators. To multiply two fixed point values, though,
     you must use this function.

     If an overflow occurs, `errno' will be set and the maximum  possible  value
     will  be  returned, but `errno' is not cleared if the operation is success-
     ful. This means that if you are going to test for overflow you  should  set
     `errno=0' before calling fixmul(). Example:

	fixed result;

	/* This will put 30000 into `result'. */
	result = fixmul(itofix(10), itofix(3000));
	/* But this overflows, and sets `errno'. */
	result = fixmul(itofix(100), itofix(3000));
	ASSERT(!errno);

RETURN VALUE
     Returns  the  clamped  result of multiplying `x' by `y', setting `errno' to
     ERANGE if there was an overflow.

SEE ALSO
     fixadd(3), fixsub(3), fixdiv(3), ex3buf(3), excustom(3),  exfixed(3),  exs-
     pline(3), exstars(3), exupdate(3)

Allegro 			  version 4.4.3 		       fixmul(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=fixmul&sektion=3&manpath=FreeBSD+Ports+15.1.quarterly>

home | help