314 lines
7.7 KiB
Groff
314 lines
7.7 KiB
Groff
.\" $NetBSD: chmod.1,v 1.28 2017/07/04 06:47:27 wiz Exp $
|
|
.\"
|
|
.\" Copyright (c) 1989, 1990, 1993, 1994
|
|
.\" The Regents of the University of California. All rights reserved.
|
|
.\"
|
|
.\" This code is derived from software contributed to Berkeley by
|
|
.\" the Institute of Electrical and Electronics Engineers, Inc.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\" 3. Neither the name of the University nor the names of its contributors
|
|
.\" may be used to endorse or promote products derived from this software
|
|
.\" without specific prior written permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" @(#)chmod.1 8.4 (Berkeley) 3/31/94
|
|
.\"
|
|
.Dd August 11, 2016
|
|
.Dt CHMOD 1
|
|
.Os
|
|
.Sh NAME
|
|
.Nm chmod
|
|
.Nd change file modes
|
|
.Sh SYNOPSIS
|
|
.Nm
|
|
.Oo
|
|
.Fl R
|
|
.Op Fl H | Fl L | Fl P
|
|
.Oc
|
|
.Op Fl fh
|
|
.Ar mode
|
|
.Ar
|
|
.Nm
|
|
.Oo
|
|
.Fl R
|
|
.Op Fl H | Fl L | Fl P
|
|
.Oc
|
|
.Op Fl fh
|
|
.Fl Fl reference=rfile
|
|
.Ar
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Nm
|
|
utility modifies the file mode bits of the listed files
|
|
as specified by the
|
|
.Ar mode
|
|
operand, or
|
|
copied from a reference
|
|
.Ar rfile ,
|
|
as specified with the
|
|
.Fl Fl reference
|
|
argument.
|
|
.Pp
|
|
The options are as follows:
|
|
.Bl -tag -width Ds
|
|
.It Fl H
|
|
If the
|
|
.Fl R
|
|
option is specified, symbolic links on the command line are followed.
|
|
(Symbolic links encountered in the tree traversal are not followed.)
|
|
.It Fl L
|
|
If the
|
|
.Fl R
|
|
option is specified, all symbolic links are followed.
|
|
.It Fl P
|
|
If the
|
|
.Fl R
|
|
option is specified, no symbolic links are followed.
|
|
.It Fl R
|
|
Change the modes of the file hierarchies rooted in the files
|
|
instead of just the files themselves.
|
|
.It Fl f
|
|
Do not display a diagnostic message or modify the exit status if
|
|
.Nm
|
|
fails to change the mode of a file.
|
|
.It Fl h
|
|
If
|
|
.Ar file
|
|
is symbolic link, the mode of the link is changed.
|
|
.El
|
|
.Pp
|
|
The
|
|
.Fl H ,
|
|
.Fl L
|
|
and
|
|
.Fl P
|
|
options are ignored unless the
|
|
.Fl R
|
|
option is specified.
|
|
In addition, these options override each other and the
|
|
command's actions are determined by the last one specified.
|
|
The default is as if the
|
|
.Fl P
|
|
option had been specified.
|
|
.Pp
|
|
Only the owner of a file or the super-user is permitted to change
|
|
the mode of a file.
|
|
.Sh EXIT STATUS
|
|
.Ex -std chmod
|
|
.Sh MODES
|
|
Modes may be absolute or symbolic.
|
|
An absolute mode is an octal number constructed by
|
|
.Em or Ap ing
|
|
the following values:
|
|
.Pp
|
|
.Bl -tag -width 6n -compact -offset indent
|
|
.It Li 4000
|
|
set-user-ID-on-execution
|
|
.It Li 2000
|
|
set-group-ID-on-execution
|
|
.It Li 1000
|
|
sticky bit, see
|
|
.Xr chmod 2
|
|
.It Li 0400
|
|
read by owner
|
|
.It Li 0200
|
|
write by owner
|
|
.It Li 0100
|
|
execute (or search for directories) by owner
|
|
.It Li 0070
|
|
read, write, execute/search by group
|
|
.It Li 0007
|
|
read, write, execute/search by others
|
|
.El
|
|
.Pp
|
|
The read, write, and execute/search values for group and others
|
|
are encoded as described for owner.
|
|
.Pp
|
|
The symbolic mode is described by the following grammar:
|
|
.Bd -literal -offset indent
|
|
mode ::= clause [, clause ...]
|
|
clause ::= [who ...] [action ...] last_action
|
|
action ::= op [perm ...]
|
|
last_action ::= op [perm ...]
|
|
who ::= a | u | g | o
|
|
op ::= + | \- | =
|
|
perm ::= r | s | t | w | x | X | u | g | o
|
|
.Ed
|
|
.Pp
|
|
The
|
|
.Ar who
|
|
symbols ``u'', ``g'', and ``o'' specify the user, group, and other parts
|
|
of the mode bits, respectively.
|
|
The
|
|
.Ar who
|
|
symbol ``a'' is equivalent to ``ugo''.
|
|
.Pp
|
|
The
|
|
.Ar perm
|
|
symbols represent the portions of the mode bits as follows:
|
|
.Pp
|
|
.Bl -tag -width Ds -compact -offset indent
|
|
.It r
|
|
The read bits.
|
|
.It s
|
|
The set-user-ID-on-execution and set-group-ID-on-execution bits.
|
|
.It t
|
|
The sticky bit.
|
|
.It w
|
|
The write bits.
|
|
.It x
|
|
The execute/search bits.
|
|
.It X
|
|
The execute/search bits if the file is a directory or any of the
|
|
execute/search bits are set in the original (unmodified) mode.
|
|
Operations with the
|
|
.Ar perm
|
|
symbol ``X'' are only meaningful in conjunction with the
|
|
.Ar op
|
|
symbol ``+'', and are ignored in all other cases.
|
|
.It u
|
|
The user permission bits in the mode of the original file.
|
|
.It g
|
|
The group permission bits in the mode of the original file.
|
|
.It o
|
|
The other permission bits in the mode of the original file.
|
|
.El
|
|
.Pp
|
|
The
|
|
.Ar op
|
|
symbols represent the operation performed, as follows:
|
|
.Bl -tag -width 4n
|
|
.It +
|
|
If no value is supplied for
|
|
.Ar perm ,
|
|
the ``+'' operation has no effect.
|
|
If no value is supplied for
|
|
.Ar who ,
|
|
each permission bit specified in
|
|
.Ar perm ,
|
|
for which the corresponding bit in the file mode creation mask
|
|
is clear, is set.
|
|
Otherwise, the mode bits represented by the specified
|
|
.Ar who
|
|
and
|
|
.Ar perm
|
|
values are set.
|
|
.It \&\-
|
|
If no value is supplied for
|
|
.Ar perm ,
|
|
the ``\-'' operation has no effect.
|
|
If no value is supplied for
|
|
.Ar who ,
|
|
each permission bit specified in
|
|
.Ar perm ,
|
|
for which the corresponding bit in the file mode creation mask
|
|
is clear, is cleared.
|
|
Otherwise, the mode bits represented by the specified
|
|
.Ar who
|
|
and
|
|
.Ar perm
|
|
values are cleared.
|
|
.It =
|
|
The mode bits specified by the
|
|
.Ar who
|
|
value are cleared, or, if no who value is specified, the owner, group
|
|
and other mode bits are cleared.
|
|
Then, if no value is supplied for
|
|
.Ar who ,
|
|
each permission bit specified in
|
|
.Ar perm ,
|
|
for which the corresponding bit in the file mode creation mask
|
|
is clear, is set.
|
|
Otherwise, the mode bits represented by the specified
|
|
.Ar who
|
|
and
|
|
.Ar perm
|
|
values are set.
|
|
.El
|
|
.Pp
|
|
Each
|
|
.Ar clause
|
|
specifies one or more operations to be performed on the mode
|
|
bits, and each operation is applied to the mode bits in the
|
|
order specified.
|
|
.Pp
|
|
Operations upon the other permissions only (specified by the symbol
|
|
``o'' by itself), in combination with the
|
|
.Ar perm
|
|
symbols ``s'' or ``t'', are ignored.
|
|
.Sh EXAMPLES
|
|
.Bl -tag -width "u=rwx,go=u-w" -compact
|
|
.It Li 644
|
|
make a file readable by anyone and writable by the owner only.
|
|
.Pp
|
|
.It Li go-w
|
|
deny write permission to group and others.
|
|
.Pp
|
|
.It Li =rw,+X
|
|
set the read and write permissions to the usual defaults, but
|
|
retain any execute permissions that are currently set.
|
|
.Pp
|
|
.It Li +X
|
|
make a directory or file searchable/executable by everyone if it is
|
|
already searchable/executable by anyone.
|
|
.Pp
|
|
.It Li 755
|
|
.It Li u=rwx,go=rx
|
|
.It Li u=rwx,go=u-w
|
|
make a file readable/executable by everyone and writable by the owner only.
|
|
.Pp
|
|
.It Li go=
|
|
clear all mode bits for group and others.
|
|
.Pp
|
|
.It Li g=u-w
|
|
set the group bits equal to the user bits, but clear the group write bit.
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr chflags 1 ,
|
|
.Xr install 1 ,
|
|
.Xr chmod 2 ,
|
|
.Xr stat 2 ,
|
|
.Xr umask 2 ,
|
|
.Xr fts 3 ,
|
|
.Xr setmode 3 ,
|
|
.Xr symlink 7 ,
|
|
.Xr chown 8
|
|
.Sh STANDARDS
|
|
The
|
|
.Nm
|
|
utility is expected to be
|
|
.St -p1003.2-92
|
|
compatible with the exception of the
|
|
.Ar perm
|
|
symbol
|
|
.Dq t
|
|
which is not included in that standard.
|
|
.Sh HISTORY
|
|
A
|
|
.Nm
|
|
utility appeared in
|
|
.At v1 .
|
|
.Sh BUGS
|
|
There's no
|
|
.Ar perm
|
|
option for the naughty bits.
|