When using POSIXly functions, we need to define _POSIX_C_SOURCE, at

 *

 */

#define _POSIX_C_SOURCE 2	/* On VMS, you need to define this to get

				   the declaration of fileno().  The value

				   2 is to make sure no function defined

				   in POSIX-2 is left undefined. */

#include <stdio.h>

#include <stdlib.h>

#include <string.h>