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fixadd(3) Allegro manual fixadd(3) NAME fixadd - Safe function to add fixed point numbers clamping overflow. Alle- gro 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 oper- ator, 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(3), fixmul(3), fixdiv(3) Allegro version 4.4.3 fixadd(3)
NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | SEE ALSO
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