rintl

       est integer

SYNOPSIS
       #include <math.h>

       double nearbyint(double x);
       float nearbyintf(float x);
       long double nearbyintl(long double x);

       double rint(double x);
       float rintf(float x);
       long double rintl(long double x);

       Link with -lm.

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       nearbyint(), nearbyintf(), nearbyintl(): _XOPEN_SOURCE >= 600 ||
       _ISOC99_SOURCE; or cc -std=c99
       rint(): _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 500 ||
       _ISOC99_SOURCE; or cc -std=c99
       rintf(), rintl(): _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600
       || _ISOC99_SOURCE; or cc -std=c99

DESCRIPTION
       The  nearbyint()  functions round their argument to an integer value in
       floating-point format, using the current rounding direction  (see  fes-
       etround(3)) and without raising the inexact exception.

       The  rint() functions do the same, but will raise the inexact exception
       (FE_INEXACT, checkable via fetestexcept(3)) when the result differs  in
       value from the argument.

RETURN VALUE
       These functions return the rounded integer value.

       If x is integral, +0, -0, NaN, or infinite, x itself is returned.

ERRORS
       No  errors  occur.  POSIX.1-2001 documents a range error for overflows,
       but see NOTES.

CONFORMING TO
       C99, POSIX.1-2001.

NOTES
       SUSv2 and POSIX.1-2001 contain text about  overflow  (which  might  set
       errno  to ERANGE, or raise an FE_OVERFLOW exception).  In practice, the
       result cannot overflow on any current machine, so  this  error-handling
       stuff is just nonsense.  (More precisely, overflow can happen only when
       the maximum value of the exponent is smaller than the  number  of  man-
       tissa bits.  For the IEEE-754 standard 32-bit and 64-bit floating-point
       numbers the maximum value of the exponent is 128 (respectively,  1024),
       and the number of mantissa bits is 24 (respectively, 53).)


                                  2008-08-05                           RINT(3)