CHMOD(2) CHMOD(2)
NAME
chmod - change mode of file
SYNOPSIS
chmod(name, mode)
char *name;
DESCRIPTION
The file whose name is given as the null-terminated string
pointed to by name has its mode changed to mode. Modes are
constructed by ORing together some combination of the fol-
lowing:
04000 set user ID on execution
02000 set group ID on execution
01000 save text image after execution
00400 read by owner
00200 write by owner
00100 execute (search on directory) by owner
00070 read, write, execute (search) by group
00007 read, write, execute (search) by others
If an executable file is set up for sharing (-n or -i option
of ld(1)) then mode 1000 prevents the system from abandoning
the swap-space image of the program-text portion of the file
when its last user terminates. Thus when the next user of
the file executes it, the text need not be read from the
file system but can simply be swapped in, saving time.
Ability to set this bit is restricted to the super-user
since swap space is consumed by the images; it is only worth
while for heavily used commands.
Only the owner of a file (or the super-user) may change the
mode. Only the super-user can set the 1000 mode.
SEE ALSO
chmod(1)
DIAGNOSTIC
Zero is returned if the mode is changed; -1 is returned if
name cannot be found or if current user is neither the owner
of the file nor the super-user.
ASSEMBLER
(chmod = 15.)
sys chmod; name; mode