NAME

       lrint, lrintf, lrintl - round to nearest integer value using current rounding direction

SYNOPSIS

       #include <math.h>

       long lrint(double x);
       long lrintf(float x);
       long lrintl(long double x);

DESCRIPTION

       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, a domain error shall occur and  an
       unspecified value is returned.

       If  the correct value is negative and too large to represent as a long, a domain error shall occur and an
       unspecified value is returned.

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.

       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 argument, they raise the inexact floating-point exception.

FUTURE DIRECTIONS

       None.

SEE ALSO

       feclearexcept() , fetestexcept() , llrint()  ,  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 .