lround(), lroundf(), lroundl()

Round a floating-point number to the nearest integer value

Synopsis:

#include <math.h>

long int lround( double x );

long int lroundf( float x );

long int lroundl( long double x );

Arguments:

x: The number that you want to round.

Library:

libm

Use the -l m option to qcc to link against this library.

Description:

The lround(), lroundf(), and lroundl() functions round a floating-point number to the nearest integer value, rounding halfway cases away from zero, regardless of the current rounding direction.

To check for error situations, use feclearexcept() and fetestexcept(). For example:

Call feclearexcept(FE_ALL_EXCEPT) before calling lround(), lroundf(), or lroundl().
On return, if fetestexcept(FE_ALL_EXCEPT) is nonzero, then an error has occurred.

Returns:

The rounded integer value.

If:	These functions return:	Errors:
`x` is ±Inf	An unspecified value	FE_INVALID
`x` is NaN	An unspecified value	FE_INVALID
The correct value is too large to represent as a long	An unspecified value	FE_INVALID

These functions raise FE_INEXACT if the FPU reports that the result can't be exactly represented as a floating-point number.

Classification:

ANSI, POSIX 1003.1

Safety:
Cancellation point	No
Interrupt handler	No
Signal handler	No
Thread	Yes