huschi.net

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  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 imple-
       mentation-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  implementa-
       tion-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 vol-
       ume  of  IEEE Std 1003.1-2001,  Section 4.18, Treatment of Error Condi-
       tions 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,  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(3P)