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 (con-
       sult the corresponding 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  remquo(),  remquof(), and remquol() functions shall compute the same remainder as the remainder(), remainderf(), and
       remainderl() functions, 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 implementa-
       tion-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  sup-
       ported), or an implementation-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.

SEE ALSO
       feclearexcept(), fetestexcept(), remainder(), the Base Definitions volume of IEEE Std 1003.1-2001, Section  4.18,  Treat-
       ment of Error Conditions for Mathematical Functions, <math.h>

COPYRIGHT
       Portions  of  this  text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for
       Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6,  Copy-
       right (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.open-
       group.org/unix/online.html .



IEEE/The Open Group                                           2003                                                    REMQUO(3P)