REMQUO(3) Library Functions Manual REMQUO(3)

remquo remquof remquol — remainder functions

#include <math.h>

double remquo(double x, double y, int *quo);
float remquof(float x, float y, int *quo);
long double remquol(long double x, long double y, int *quo);

The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here and the ISO C standard is unintentional. This volume of IEEE Std 1003.1-2001 (“POSIX.1”) defers to the ISO C standard.

The remquo (), (), and () functions shall compute the same remainder as the remainder(3), remainderf(3), and remainderl(3) functions, respectively. In the object pointed to by , they store a value whose sign is the sign of x / y and whose magnitude is congruent modulo 2 n to the magnitude of the integral quotient of x / y, where n is an implementation-defined integer greater than or equal to 3.

An application wishing to check for error situations should set errno to zero and call (FE_ALL_EXCEPT) before calling these functions. On return, if errno is non-zero or (FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW) is non-zero, an error has occurred.

These functions shall return x REM y.

If x or y is NaN, a NaN shall be returned.

If x is ±Inf or y is zero and the other argument is non-NaN, a domain error shall occur, and either a NaN (if supported), or an implementation-defined value shall be returned.

These functions shall fail if:

[MX] The x argument is ±Inf, or the y argument is ±0 and the other argument is non-NaN.

If the integer expression (math_errhandling & MATH_ERRNO) is non-zero, then errno shall be set to [EDOM]. If the integer expression (math_errhandling & MATH_ERREXCEPT) is non-zero, then the invalid floating-point exception shall be raised.

None.

On error, the expressions (math_errhandling & MATH_ERRNO) and (math_errhandling & MATH_ERREXCEPT) are independent of each other, but at least one of them must be non-zero.

These functions are intended for implementing argument reductions which can exploit a few low-order bits of the quotient. Note that x may be so large in magnitude relative to y that an exact representation of the quotient is not practical.

None.

feclearexcept(3) , fetestexcept(3) , remainder(3) , the Base Definitions volume of IEEE Std 1003.1-2001 (“POSIX.1”), xbd_chap04(7), <math.h>

First released in Issue 6. Derived from the ISO/IEC 9899:1999 (“ISO C99”) standard.

footer end

December 6, 2001 posix.fail