plucky (3) fixdiv.3alleg4.gz

NAME

       fixdiv - Fixed point division. Allegro game programming library.

SYNOPSIS

       #include <allegro.h>

       fixed fixdiv(fixed x, fixed y);

DESCRIPTION

       A  fixed point value can be divided by an integer with the normal `/' operator. To divide two fixed point
       values, though, you must use this function. If a division by zero 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  division  by  zero  you  should  set  `errno=0'  before  calling
       fixdiv(). Example:

          fixed result;
          /* This will put 0.06060 `result'. */
          result = fixdiv(itofix(2), itofix(33));
          /* This will put 0 into `result'. */
          result = fixdiv(0, itofix(-30));
          /* Sets `errno' and puts -32768 into `result'. */
          result = fixdiv(itofix(-100), itofix(0));
          ASSERT(!errno); /* This will fail. */

RETURN VALUE

       Returns the result of dividing `x' by `y'. If `y' is zero, returns the maximum possible fixed point value
       and sets `errno' to ERANGE.

SEE ALSO

       fixadd(3alleg4), fixsub(3alleg4), fixmul(3alleg4), exfixed(3alleg4)