umask.2 (2010 09)

u
umask(2) umask(2)
NAME
umask - set and get file creation mask
SYNOPSIS
#include <sys/stat.h>
mode_t umask(mode_t cmask);
DESCRIPTION
umask() sets the process’s file mode creation mask to cmask and returns the previous value of the mask.
Only the file access permission bits of the masks are used.
The bits set in cmask specify which permission bits to turn off in the mode of the created file, and should
be specified using the symbolic values defined in stat (5).
EXAMPLES
The following creates a file named
path
in the current directory with permissions
S_IRWXU|S_IRGRP|S_IXGRP
, so that the file can be written only by its owner, and can be read or exe-
cuted only by the owner or processes with group permission, even though group write permission and all
permissions for others are passed in to
creat().
#include <sys/types.h>
#include <sys/stat.h>
int fildes;
(void) umask(S_IWGRP|S_IRWXO);
fildes = creat("path", S_IRWXU|S_IRWXG|S_IRWXO);
RETURN VALUE
The previous value of the file mode creation mask is returned.
SEE ALSO
mkdir(1), sh(1), mknod(1M), chmod(2), creat(2), mknod(2), open(2).
STANDARDS CONFORMANCE
umask(): AES, SVID2, SVID3, XPG2, XPG3, XPG4, FIPS 151-2, POSIX.1
HP-UX 11i Version 3: September 2010 − 1 − Hewlett-Packard Company 1