gnulib/doc/func.texi

@node func
@section func

@mindex func
The @code{func} module makes sure that you can use the predefined
identifier @code{__func__} as defined by C99 in your code.

A small example is:

@smallexample
#include <config.h>
#include <stdio.h> /* for printf */

int main (void)
@{
    printf ("%s: hello world\n", __func__);
@}
@end smallexample

Note that @code{sizeof} cannot be applied to @code{__func__}: On SunPRO C
compiler, @code{sizeof __func__} evaluates to 0.