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LLRINT(3P)                 POSIX Programmer's Manual                LLRINT(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
       llrint, llrintf, llrintl -- round to the nearest  integer  value  using
       current rounding direction
SYNOPSIS
       #include <math.h>
       long long llrint(double x);
       long long llrintf(float x);
       long long llrintl(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, rounding according to the current rounding direction.
       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 domain error shall occur, and an  unspecified  value  is
       returned.
       If  x  is  +Inf, a domain error shall occur and an unspecified value is
       returned.
       If x is -Inf, a domain error shall occur and an  unspecified  value  is
       returned.
       If  the  correct value is positive and too large to represent as a long
       long, an unspecified value shall be returned.  On systems that  support
       the IEC 60559 Floating-Point option, a domain error shall occur; other-
       wise, a domain error may occur.
       If the correct value is negative and too large to represent as  a  long
       long,  an unspecified value shall be returned.  On systems that support
       the IEC 60559 Floating-Point option, a domain error shall occur; other-
       wise, a domain error may occur.
ERRORS
       These functions shall fail if:
       Domain Error
                   The x argument is NaN or +-Inf, or the correct value is not
                   representable as an integer.
                   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 correct value is not representable as an integer.
                   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 provide  floating-to-integer  conversions.  They  round
       according  to  the  current rounding direction. If the rounded value is
       outside the range of the return type, the numeric result is unspecified
       and  the invalid floating-point exception is raised. When they raise no
       other floating-point exception and the result differs  from  the  argu-
       ment, they raise the inexact floating-point exception.
FUTURE DIRECTIONS
       None.
SEE ALSO
       feclearexcept(), fetestexcept(), lrint()
       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                           LLRINT(3P)