CHMOD(1-BSD) RISC/os Reference Manual CHMOD(1-BSD)
NAME
chmod - change mode
SYNOPSIS
chmod [ -Rf ] mode file ...
DESCRIPTION
The mode of each named file is changed according to mode,
which may be absolute or symbolic. An absolute mode is an
octal number constructed from the OR of the following modes:
4000 set user ID on execution
2000 set group ID on execution
1000 sticky bit, see chmod(2)
0400 read by owner
0200 write by owner
0100 execute (search in directory) by owner
0070 read, write, execute (search) by group
0007 read, write, execute (search) by others
A symbolic mode has the form:
[who] op permission [op permission] ...
The who part is a combination of the letters u (for user's
permissions), g (group) and o (other). The letter a stands
for all, or ugo. If who is omitted, the default is a but
the setting of the file creation mask (see umask(2)) is
taken into account.
Op can be + to add permission to the file's mode, - to take
away permission and = to assign permission absolutely (all
other bits will be reset).
Permission is any combination of the letters r (read), w
(write), x (execute), X (set execute only if file is a
directory or some other execute bit is set), s (set owner or
group id) and t (save text - sticky). Letters u, g, or o
indicate that permission is to be taken from the current
mode. Omitting permission is only useful with = to take away
all permissions.
When the -R option is given, chmod recursively descends its
directory arguments setting the mode for each file as
described above. When symbolic links are encountered, their
mode is not changed and they are not traversed.
If the -f option is given, chmod will not complain if it
fails to change the mode on a file.
EXAMPLES
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CHMOD(1-BSD) RISC/os Reference Manual CHMOD(1-BSD)
The first example denies write permission to others, the
second makes a file executable by all if it is executable by
anyone:
chmod o-w file
chmod +X file
Multiple symbolic modes separated by commas may be given.
Operations are performed in the order specified. The letter
s is only useful with u or g.
Only the owner of a file (or the super-user) may change its
mode.
SEE ALSO
ls(1), chmod(2), stat(2), umask(2), chown(8)
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