/*
 * Sample program for umask system call - No.60
 *
 * umask - set file creation mask
 *
 * Synopsis
 *     #include <sys/types.h>
 *     #include <sys/stat.h>
 *
 *     mode_t umask(mode_t mask);
 *
 * Description
 *     umask sets the umask to mask & 0777.
 *
 *     The umask is used by open(2) to set initial file permissions
 *     on a newly-created file. Specifically, permissions in the
 *     umask are turned off from the mode argument to open(2)
 *     (so, for example, the common umask default value of 022 results
 *     in new files being created with permissions 0666 & ~022 = 0644
 *     = rw-r--r-- in the usual case where the mode is specified as
 *     0666).
 *
 * Retrun value
 *     This system call always succeeds and the previous value of
 *     the mask is returned.
 */

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>

main()
{
	mode_t umask_bak;

	umask_bak = umask(0);
	system("umask -p");
	system("umask -S");
	umask(umask_bak);
	system("umask -p");
	system("umask -S");

	exit(0);
}