|UMASK(2)||System Calls Manual||UMASK(2)|
umask — set file
creation mode mask
Standard C Library (libc, -lc)
routine sets the process's file mode creation mask to
numask and returns the previous value of the mask. The
9 low-order access permission bits of numask are used
by system calls, including open(2),
mkdir(2), and mkfifo(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
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.
The previous value of the file mode mask is returned by the call.
umask() system call is always
umask() system call is expected to
conform to IEEE Std 1003.1-1990
umask() function appeared in
Version 7 AT&T UNIX.
|June 4, 1993||Debian|