# remquof(3) [posix man page]

```REMQUO(P)						     POSIX Programmer's Manual							 REMQUO(P)

NAME
remquo, remquof, remquol - remainder functions

SYNOPSIS
#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);

DESCRIPTION
The  remquo(), remquof(), and remquol() functions shall compute the same remainder as the remainder(), remainderf(), and remainderl() func-
tions, respectively. In the object pointed to by quo, 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 feclearexcept(FE_ALL_EXCEPT) before calling these
functions.  On return, if errno is non-zero or fetestexcept(FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW) is non-zero,  an  error
has occurred.

RETURN VALUE
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 implemen-
tation-defined value shall be returned.

ERRORS
These functions shall fail if:

Domain Error
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.

The following sections are informative.

EXAMPLES
None.

APPLICATION USAGE
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.

RATIONALE
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.

FUTURE DIRECTIONS
None.

feclearexcept() , fetestexcept() , remainder() , the Base Definitions volume of IEEE Std 1003.1-2001, Section 4.18, Treatment of Error Con-
ditions for Mathematical Functions, <math.h>

Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technol-
ogy -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and  the  original  IEEE
and  The  Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained
online at http://www.opengroup.org/unix/online.html .

IEEE/The Open Group						       2003								 REMQUO(P)```

## Check Out this Related Man Page

```REMQUO(3P)						     POSIX Programmer's Manual							REMQUO(3P)

PROLOG
This  manual page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (consult the correspond-
ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

NAME
remquo, remquof, remquol -- remainder functions

SYNOPSIS
#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);

DESCRIPTION
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 POSIX.1-2008 defers to the ISO C standard.

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

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

RETURN VALUE
These functions shall return x REM y.

On systems that do not support the IEC 60559 Floating-Point option, if y is zero, it  is  implementation-defined  whether  a  domain  error
occurs or zero is returned.

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 a NaN shall be returned.

ERRORS
These functions shall fail if:

Domain Error
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.

These functions may fail if:

Domain Error
The y argument is zero.

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.

The following sections are informative.

EXAMPLES
None.

APPLICATION USAGE
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.

RATIONALE
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.

FUTURE DIRECTIONS
None.

feclearexcept(), fetestexcept(), remainder()

The Base Definitions volume of POSIX.1-2008, Section 4.19, Treatment of Error Conditions for Mathematical Functions, <math.h>