### 1.58 `trunc`, `truncf`—round to integer, towards zero ¶

Synopsis

    #include <math.h>
    double trunc(double x);
    float truncf(float x);

Description
The `trunc` functions round their argument to the integer value, in floating format, nearest to but no larger in magnitude than the argument, regardless of the current rounding direction. (While the "inexact" floating-point exception behavior is unspecified by the C standard, the `trunc` functions are written so that "inexact" is not raised if the result does not equal the argument, which behavior is as recommended by IEEE 754 for its related functions.)

Returns
x truncated to an integral value.

Portability
ANSI C, POSIX