man fixdiv () - Fixed point division. Allegro game programming library.
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(3)); /* 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.