iOS Developer Library Developer
Search
ADC Home > Reference Library > Reference > Mac OS X > Mac OS X Man Pages

 

This document is a Mac OS X manual page. Manual pages are a command-line technology for providing documentation. You can view these manual pages locally using the man(1) command. These manual pages come from many different sources, and thus, have a variety of writing styles.

For more information about the manual page format, see the manual page for manpages(5).



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 permission
     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
Feedback