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NEARBYINT(3P)              POSIX Programmer's Manual             NEARBYINT(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
       nearbyint, nearbyintf, nearbyintl - floating-point rounding functions
SYNOPSIS
       #include <math.h>
       double nearbyint(double x);
       float nearbyintf(float x);
       long double nearbyintl(long double x);

DESCRIPTION
       These functions shall round their  argument  to  an  integer  value  in
       floating-point format, using the current rounding direction and without
       raising the inexact floating-point exception.
       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
       Upon successful completion, these functions shall  return  the  rounded
       integer value.
       If x is NaN, a NaN shall be returned.
       If x is +-0, +-0 shall be returned.
       If x is +-Inf, x shall be returned.
       If  the  correct  value would cause overflow, a range error shall occur
       and nearbyint(), nearbyintf(), and nearbyintl() shall return the  value
       of  the  macro  +-HUGE_VAL, +-HUGE_VALF, and +-HUGE_VALL (with the same
       sign as x), respectively.
ERRORS
       These functions shall fail if:
       Range Error
              The result would cause an overflow.
       If the integer expression (math_errhandling & MATH_ERRNO) is  non-zero,
       then  errno  shall  be  set  to  [ERANGE].  If  the  integer expression
       (math_errhandling & MATH_ERREXCEPT)  is  non-zero,  then  the  overflow
       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
       None.
FUTURE DIRECTIONS
       None.
SEE ALSO
       feclearexcept(),   fetestexcept(),   the  Base  Definitions  volume  of
       IEEE Std 1003.1-2001, Section 4.18, Treatment 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, 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                        NEARBYINT(3P)