fixdiv

Section: Allegro manual (3)
Updated: version 4.2.2
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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(3), fixsub(3), fixmul(3), exfixed(3)