posix man page for lroundf

LROUND(P)						     POSIX Programmer's Manual							 LROUND(P)

NAME
       lround, lroundf, lroundl - round to nearest integer value

SYNOPSIS
       #include <math.h>

       long lround(double x);
       long lroundf(float x);
       long lroundl(long double x);

DESCRIPTION
       These  functions  shall round their argument to the nearest integer value, rounding halfway cases away from zero, regardless of 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 differ from the lrint() functions in the default rounding direction, with the lround()  functions  rounding  halfway  cases
       away  from  zero  and needing not to raise the inexact floating-point exception for non-integer arguments that round to within the range of
       the return type.

FUTURE DIRECTIONS
       None.

SEE ALSO
       feclearexcept() , fetestexcept() , llround() , the Base Definitions volume of IEEE Std 1003.1-2001, Section 4.18, Treatment of Error Condi-
       tions 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 Technol-
       ogy -- 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								 LROUND(P)