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ROUND(3P)                  POSIX Programmer's Manual                 ROUND(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
       round, roundf, roundl -- round to the nearest integer value in a float-
       ing-point format
SYNOPSIS
       #include <math.h>
       double round(double x);
       float roundf(float x);
       long double roundl(long double x);
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.
       These functions shall round their argument to the nearest integer value
       in  floating-point  format,  rounding  halfway  cases  away  from zero,
       regardless of the current rounding direction.
RETURN VALUE
       Upon successful completion, these functions shall  return  the  rounded
       integer value.  The result shall have the same sign as x.
       If x is NaN, a NaN shall be returned.
       If x is +-0 or +-Inf, x shall be returned.
ERRORS
       No errors are defined.
       The following sections are informative.
EXAMPLES
       None.
APPLICATION USAGE
       The  integral value returned by these functions need not be expressible
       as an intmax_t.  The return value should be tested before assigning  it
       to  an  integer type to avoid the undefined results of an integer over-
       flow.
       These functions may raise the inexact floating-point exception  if  the
       result differs in value from the argument.
RATIONALE
       None.
FUTURE DIRECTIONS
       None.
SEE ALSO
       feclearexcept(), fetestexcept()
       The Base Definitions volume of POSIX.1-2008, Section 4.19, 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, 2013 Edition, Standard for Information Technology
       -- Portable Operating System Interface (POSIX),  The  Open  Group  Base
       Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri-
       cal and Electronics Engineers,  Inc  and  The  Open  Group.   (This  is
       POSIX.1-2008  with  the  2013  Technical Corrigendum 1 applied.) 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.unix.org/online.html .
       Any  typographical  or  formatting  errors that appear in this page are
       most likely to have been introduced during the conversion of the source
       files  to  man page format. To report such errors, see https://www.ker-
       nel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group                  2013                            ROUND(3P)