diff options
Diffstat (limited to 'man2/umask.2')
| -rw-r--r-- | man2/umask.2 | 30 |
1 files changed, 15 insertions, 15 deletions
diff --git a/man2/umask.2 b/man2/umask.2 index c920b55..bfea2e6 100644 --- a/man2/umask.2 +++ b/man2/umask.2 @@ -11,7 +11,7 @@ .\" <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 2023-03-30 "Linux man-pages 6.05.01" +.TH umask 2 2023-10-31 "Linux man-pages 6.7" .SH NAME umask \- set file mode creation mask .SH LIBRARY @@ -20,7 +20,7 @@ Standard C library .SH SYNOPSIS .nf .B #include <sys/stat.h> -.PP +.P .BI "mode_t umask(mode_t " mask ); .fi .SH DESCRIPTION @@ -30,7 +30,7 @@ sets the calling process's file mode creation mask (umask) to & 0777 (i.e., only the file permission bits of .I mask are used), and returns the previous value of the mask. -.PP +.P The umask is used by .BR open (2), .BR mkdir (2), @@ -45,7 +45,7 @@ argument to .BR open (2) and .BR mkdir (2). -.PP +.P Alternatively, if the parent directory has a default ACL (see .BR acl (5)), the umask is ignored, the default ACL is inherited, @@ -54,23 +54,23 @@ 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 +.P .in +4n .EX u::rwx,g::r-x,o::r-x .EE .in -.PP +.P 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 +.P The constants that should be used to specify .I mask are described in .BR inode (7). -.PP +.P The typical default value for the process umask is .BR S_IWGRP " | " S_IWOTH (octal 022). @@ -79,22 +79,22 @@ In the usual case where the argument to .BR open (2) is specified as: -.PP +.P .in +4n .EX .BR S_IRUSR " | " S_IWUSR " | " S_IRGRP " | " S_IWGRP " | " S_IROTH " | " S_IWOTH .EE .in -.PP +.P (octal 0666) when creating a new file, the permissions on the resulting file will be: -.PP +.P .in +4n .EX .BR S_IRUSR " | " S_IWUSR " | " S_IRGRP " | " S_IROTH .EE .in -.PP +.P (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 @@ -109,7 +109,7 @@ A child process created via inherits its parent's umask. The umask is left unchanged by .BR execve (2). -.PP +.P It is impossible to use .BR umask () to fetch a process's umask without at the same time changing it. @@ -118,7 +118,7 @@ A second call to would then be needed to restore the umask. The nonatomicity of these two steps provides the potential for races in multithreaded programs. -.PP +.P Since Linux 4.7, the umask of any process can be viewed via the .I Umask field of @@ -126,7 +126,7 @@ field of Inspecting this field in .I /proc/self/status allows a process to retrieve its umask without at the same time changing it. -.PP +.P The umask setting also affects the permissions assigned to POSIX IPC objects .RB ( mq_open (3), .BR sem_open (3), |