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Diffstat (limited to 'man2/umask.2')
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diff --git a/man2/umask.2 b/man2/umask.2 deleted file mode 100644 index 07e0b5e76..000000000 --- a/man2/umask.2 +++ /dev/null @@ -1,149 +0,0 @@ -.\" Copyright (c) 2006, 2008, Michael Kerrisk <mtk.manpages@gmail.com> -.\" (A few fragments remain from an earlier (1992) version written in -.\" 1992 by Drew Eckhardt <drew@cs.colorado.edu>.) -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.\" Modified by Michael Haardt <michael@moria.de> -.\" Modified Sat Jul 24 12:51:53 1993 by Rik Faith <faith@cs.unc.edu> -.\" Modified Tue Oct 22 22:39:04 1996 by Eric S. Raymond <esr@thyrsus.com> -.\" Modified Thu May 1 06:05:54 UTC 1997 by Nicolás Lichtmaier -.\" <nick@debian.com> with Lars Wirzenius <liw@iki.fi> suggestion -.\" 2006-05-13, mtk, substantial rewrite of description of 'mask' -.\" 2008-01-09, mtk, a few rewrites and additions. -.TH umask 2 (date) "Linux man-pages (unreleased)" -.SH NAME -umask \- set file mode creation mask -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <sys/stat.h> -.PP -.BI "mode_t umask(mode_t " mask ); -.fi -.SH DESCRIPTION -.BR umask () -sets the calling process's file mode creation mask (umask) to -.I mask -& 0777 (i.e., only the file permission bits of -.I mask -are used), and returns the previous value of the mask. -.PP -The umask is used by -.BR open (2), -.BR mkdir (2), -and other system calls that create files -.\" e.g., mkfifo(), creat(), mknod(), sem_open(), mq_open(), shm_open() -.\" but NOT the System V IPC *get() calls -to modify the permissions placed on newly created files or directories. -Specifically, permissions in the umask are turned off from -the -.I mode -argument to -.BR open (2) -and -.BR mkdir (2). -.PP -Alternatively, if the parent directory has a default ACL (see -.BR acl (5)), -the umask is ignored, the default ACL is inherited, -the permission bits are set based on the inherited ACL, -and permission bits absent in the -.I mode -argument are turned off. -For example, the following default ACL is equivalent to a umask of 022: -.PP -.in +4n -.EX -u::rwx,g::r-x,o::r-x -.EE -.in -.PP -Combining the effect of this default ACL with a -.I mode -argument of 0666 (rw-rw-rw-), the resulting file permissions would be 0644 -(rw-r--r--). -.PP -The constants that should be used to specify -.I mask -are described in -.BR inode (7). -.PP -The typical default value for the process umask is -.BR S_IWGRP " | " S_IWOTH -(octal 022). -In the usual case where the -.I mode -argument to -.BR open (2) -is specified as: -.PP -.in +4n -.EX -.BR S_IRUSR " | " S_IWUSR " | " S_IRGRP " | " S_IWGRP " | " S_IROTH " | " S_IWOTH -.EE -.in -.PP -(octal 0666) when creating a new file, the permissions on the -resulting file will be: -.PP -.in +4n -.EX -.BR S_IRUSR " | " S_IWUSR " | " S_IRGRP " | " S_IROTH -.EE -.in -.PP -(because 0666 & \[ti]022 = 0644; i.e. rw\-r\-\-r\-\-). -.SH RETURN VALUE -This system call always succeeds and the previous value of the mask -is returned. -.SH STANDARDS -POSIX.1-2008. -.SH HISTORY -POSIX.1-2001, SVr4, 4.3BSD. -.SH NOTES -A child process created via -.BR fork (2) -inherits its parent's umask. -The umask is left unchanged by -.BR execve (2). -.PP -It is impossible to use -.BR umask () -to fetch a process's umask without at the same time changing it. -A second call to -.BR umask () -would then be needed to restore the umask. -The nonatomicity of these two steps provides the potential -for races in multithreaded programs. -.PP -Since Linux 4.7, the umask of any process can be viewed via the -.I Umask -field of -.IR /proc/ pid /status . -Inspecting this field in -.I /proc/self/status -allows a process to retrieve its umask without at the same time changing it. -.PP -The umask setting also affects the permissions assigned to POSIX IPC objects -.RB ( mq_open (3), -.BR sem_open (3), -.BR shm_open (3)), -FIFOs -.RB ( mkfifo (3)), -and UNIX domain sockets -.RB ( unix (7)) -created by the process. -The umask does not affect the permissions assigned -to System\ V IPC objects created by the process (using -.BR msgget (2), -.BR semget (2), -.BR shmget (2)). -.SH SEE ALSO -.BR chmod (2), -.BR mkdir (2), -.BR open (2), -.BR stat (2), -.BR acl (5) |