Visit Our UNIX and Linux User Community

fixadd(3alleg4) 						  Allegro manual						   fixadd(3alleg4)

fixadd - Safe function to add fixed point numbers clamping overflow. Allegro game programming library. SYNOPSIS
#include <allegro.h> fixed fixadd(fixed x, fixed y); DESCRIPTION
Although fixed point numbers can be added with the normal '+' integer operator, that doesn't provide any protection against overflow. If overflow is a problem, you should use this function instead. It is slower than using integer operators, but if an overflow occurs it will set `errno' and clamp the result, rather than just letting it wrap. Example: fixed result; /* This will put 5035 into `result'. */ result = fixadd(itofix(5000), itofix(35)); /* Sets `errno' and puts -32768 into `result'. */ result = fixadd(itofix(-31000), itofix(-3000)); ASSERT(!errno); /* This will fail. */ RETURN VALUE
Returns the clamped result of adding `x' to `y', setting `errno' to ERANGE if there was an overflow. SEE ALSO
fixsub(3alleg4), fixmul(3alleg4), fixdiv(3alleg4) Allegro version 4.4.2 fixadd(3alleg4)

Featured Tech Videos