umask(2) BSD System Calls Manual umask(2)
NAME
umask -- set file creation mode mask
SYNOPSIS
#include <sys/stat.h>
mode_t
umask(mode_t cmask);
DESCRIPTION
The umask() routine sets the process's file mode creation mask to cmask
and returns the previous value of the mask. The 9 low-order access per-
mission bits of cmask are used by system calls, including open(2),
mkdir(2), mkfifo(2), and mknod(2) to turn off corresponding bits
requested in file mode. (See chmod(2)). This clearing allows each user
to restrict the default access to his files.
The default mask value is S_IWGRP | S_IWOTH (022, write access for the
owner only). Child processes inherit the mask of the calling process.
RETURN VALUES
The previous value of the file mode mask is returned by the call.
ERRORS
The umask() function is always successful.
LEGACY SYNOPSIS
#include <sys/types.h>
#include <sys/stat.h>
The include file <sys/types.h> is necessary.
SEE ALSO
chmod(2), mkdir(2), mkfifo(2), mknod(2), open(2), compat(5)
STANDARDS
The umask() function call is expected to conform to IEEE Std 1003.1-1988
(``POSIX.1'').
4th Berkeley Distribution June 4, 1993 4th Berkeley Distribution
Mac OS X 10.9.1 - Generated Mon Jan 6 18:34:41 CST 2014