NAME

       fixmul - Multiplies two fixed point values together. Allegro game programming 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 successful. 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(3alleg4),  fixsub(3alleg4),  fixdiv(3alleg4),  ex3buf(3alleg4),  excustom(3alleg4),
       exfixed(3alleg4), exspline(3alleg4), exstars(3alleg4), exupdate(3alleg4)