trunc(), truncf(), truncl()

Synopsis:

#include <math.h>

double trunc(double x);

float truncf(float x);

long double truncl(long double x);

Arguments:

x: The number that you want to truncate.

Library:

libm

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

Description:

The trunc(), truncf(), and truncl() functions round their argument to the integer value, in floating format, nearest to but no larger in magnitude than the argument.

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

Call feclearexcept(FE_ALL_EXCEPT) before calling trunc(), truncf(), or truncl().
On return, if fetestexcept(FE_ALL_EXCEPT) is nonzero, then an error has occurred.

Returns:

The truncated integer value. The result has the same sign as x.

If `x` is:	These functions return:	Errors:
±0.0	`x`	—
±Inf	`x`	—
NaN	NaN	—

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