[unix-history] / usr / share / man / cat1 / chmod.0

CHMOD(1)                     BSD Reference Manual                     CHMOD(1)

N\bNA\bAM\bME\bE
     c\bch\bhm\bmo\bod\bd - change file modes

S\bSY\bYN\bNO\bOP\bPS\bSI\bIS\bS
     c\bch\bhm\bmo\bod\bd [-\b-R\bR [-\b-H\bH | -\b-L\bL | -\b-P\bP]] _\bm_\bo_\bd_\be _\bf_\bi_\bl_\be _\b._\b._\b.

D\bDE\bES\bSC\bCR\bRI\bIP\bPT\bTI\bIO\bON\bN
     The c\bch\bhm\bmo\bod\bd utility modifies the file mode bits of the listed files as
     specified by the _\bm_\bo_\bd_\be operand.

     The options are as follows:

     -\b-H\bH      If the -\b-R\bR option is specified, symbolic links on the command line
             are followed.  (Symbolic links encountered in the tree traversal
             are not followed.)

     -\b-L\bL      If the -\b-R\bR option is specified, all symbolic links are followed.

     -\b-P\bP      If the -\b-R\bR option is specified, no symbolic links are followed.

     -\b-R\bR      Change the modes of the file hierarchies rooted in the files in-
             stead of just the files themselves.

     Symbolic links do not have modes, so unless the -\b-H\bH or -\b-L\bL option is set,
     c\bch\bhm\bmo\bod\bd on a symbolic link always succeeds and has no effect.  The -\b-H\bH, -\b-L\bL
     and -\b-P\bP options are ignored unless the -\b-R\bR option is specified.  In addi-
     tion, these options override each other and the command's actions are de-
     termined by the last one specified.

     Only the owner of a file or the super-user is permitted to change the
     mode of a file.

     The c\bch\bhm\bmo\bod\bd utility exits 0 on success, and >0 if an error occurs.

M\bMO\bOD\bDE\bES\bS
     Modes may be absolute or symbolic.  An absolute mode is an octal number
     constructed by _\bo_\br_\b-_\bi_\bn_\bg the following values:

           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 (or search for directories) by owner
           0070    read, write, execute/search by group
           0007    read, write, execute/search by others

     The read, write, and execute/search values for group and others are en-
     coded as described for owner.

     The symbolic mode is described by the following grammar:

           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

     The _\bw_\bh_\bo symbols ``u'', ``g'', and ``o'' specify the user, group, and oth-
     er parts of the mode bits, respectively.  The _\bw_\bh_\bo symbol ``a'' is equiva-
     lent to ``ugo''.

     The _\bp_\be_\br_\bm symbols represent the portions of the mode bits as follows:

           r       The read bits.
           s       The set-user-ID-on-execution and set-group-ID-on-execution
                   bits.
           t       The sticky bit.
           w       The write bits.
           x       The execute/search bits.
           X       The execute/search bits if the file is a directory or any
                   of the execute/search bits are set in the original (unmodi-
                   fied) mode.  Operations with the _\bp_\be_\br_\bm symbol ``X'' are only
                   meaningful in conjunction with the _\bo_\bp symbol ``+'', and are
                   ignored in all other cases.
           u       The user permission bits in the mode of the original file.
           g       The group permission bits in the mode of the original file.
           o       The other permission bits in the mode of the original file.

     The _\bo_\bp symbols represent the operation performed, as follows:

     +     If no value is supplied for _\bp_\be_\br_\bm, the ``+'' operation has no ef-
           fect.  If no value is supplied for _\bw_\bh_\bo, each permission bit speci-
           fied in _\bp_\be_\br_\bm, for which the corresponding bit in the file mode cre-
           ation mask is clear, is set.  Otherwise, the mode bits represented
           by the specified _\bw_\bh_\bo and _\bp_\be_\br_\bm values are set.

     -     If no value is supplied for _\bp_\be_\br_\bm, the ``-'' operation has no ef-
           fect.  If no value is supplied for _\bw_\bh_\bo, each permission bit speci-
           fied in _\bp_\be_\br_\bm, for which the corresponding bit in the file mode cre-
           ation mask is clear, is cleared.  Otherwise, the mode bits repre-
           sented by the specified _\bw_\bh_\bo and _\bp_\be_\br_\bm values are cleared.

     =     The mode bits specified by the _\bw_\bh_\bo 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 _\bw_\bh_\bo, each permission
           bit specified in _\bp_\be_\br_\bm, for which the corresponding bit in the file
           mode creation mask is clear, is set.  Otherwise, the mode bits rep-
           resented by the specified _\bw_\bh_\bo and _\bp_\be_\br_\bm values are set.

     Each _\bc_\bl_\ba_\bu_\bs_\be specifies one or more operations to be performed on the mode
     bits, and each operation is applied to the mode bits in the order speci-
     fied.

     Operations upon the other permissions only (specified by the symbol ``o''
     by itself), in combination with the _\bp_\be_\br_\bm symbols ``s'' or ``t'', are ig-
     nored.

E\bEX\bXA\bAM\bMP\bPL\bLE\bES\bS
     644           make a file readable by anyone and writable by the owner
                   only.

     go-w          deny write permission to group and others.

     =rw,+X        set the read and write permissions to the usual defaults,
                   but retain any execute permissions that are currently set.

     +X            make a directory or file searchable/executable by everyone
                   if it is already searchable/executable by anyone.

     755
     u=rwx,go=rx
     u=rwx,go=u-w  make a file readable/executable by everyone and writable by
                   the owner only.


     go=           clear all mode bits for group and others.

     g=u-w         set the group bits equal to the user bits, but clear the
                   group write bit.

B\bBU\bUG\bGS\bS
     There's no _\bp_\be_\br_\bm option for the naughty bits.

S\bSE\bEE\bE A\bAL\bLS\bSO\bO
     install(1),  chmod(2),  stat(2),  umask(2),  fts(3),  setmode(3),
     symlink(7),  chown(8)

S\bST\bTA\bAN\bND\bDA\bAR\bRD\bDS\bS
     The c\bch\bhm\bmo\bod\bd utility is expected to be POSIX 1003.2 compatible with the ex-
     ception of the _\bp_\be_\br_\bm symbols ``t'' and ``X'' which are not included in
     that standard.

4.4BSD                          March 31, 1994                               3
Commit	Line	Data
32424d04 C	1	CHMOD(1) BSD Reference Manual CHMOD(1)
	2
	3	N\bNA\bAM\bME\bE
	4	c\bch\bhm\bmo\bod\bd - change file modes
	5
	6	S\bSY\bYN\bNO\bOP\bPS\bSI\bIS\bS
	7	c\bch\bhm\bmo\bod\bd [-\b-R\bR [-\b-H\bH \| -\b-L\bL \| -\b-P\bP]] _\bm_\bo_\bd_\be _\bf_\bi_\bl_\be _\b._\b._\b.
	8
	9	D\bDE\bES\bSC\bCR\bRI\bIP\bPT\bTI\bIO\bON\bN
	10	The c\bch\bhm\bmo\bod\bd utility modifies the file mode bits of the listed files as
	11	specified by the _\bm_\bo_\bd_\be operand.
	12
	13	The options are as follows:
	14
	15	-\b-H\bH If the -\b-R\bR option is specified, symbolic links on the command line
	16	are followed. (Symbolic links encountered in the tree traversal
	17	are not followed.)
	18
	19	-\b-L\bL If the -\b-R\bR option is specified, all symbolic links are followed.
	20
	21	-\b-P\bP If the -\b-R\bR option is specified, no symbolic links are followed.
	22
	23	-\b-R\bR Change the modes of the file hierarchies rooted in the files in-
	24	stead of just the files themselves.
	25
	26	Symbolic links do not have modes, so unless the -\b-H\bH or -\b-L\bL option is set,
	27	c\bch\bhm\bmo\bod\bd on a symbolic link always succeeds and has no effect. The -\b-H\bH, -\b-L\bL
	28	and -\b-P\bP options are ignored unless the -\b-R\bR option is specified. In addi-
	29	tion, these options override each other and the command's actions are de-
	30	termined by the last one specified.
	31
	32	Only the owner of a file or the super-user is permitted to change the
	33	mode of a file.
	34
	35	The c\bch\bhm\bmo\bod\bd utility exits 0 on success, and >0 if an error occurs.
	36
	37	M\bMO\bOD\bDE\bES\bS
	38	Modes may be absolute or symbolic. An absolute mode is an octal number
	39	constructed by _\bo_\br_\b-_\bi_\bn_\bg the following values:
	40
	41	4000 set-user-ID-on-execution
	42	2000 set-group-ID-on-execution
	43	1000 sticky bit, see chmod(2)
	44	0400 read by owner
	45	0200 write by owner
	46	0100 execute (or search for directories) by owner
	47	0070 read, write, execute/search by group
	48	0007 read, write, execute/search by others
	49
	50	The read, write, and execute/search values for group and others are en-
	51	coded as described for owner.
	52
	53	The symbolic mode is described by the following grammar:
	54
	55	mode ::= clause [, clause ...]
	56	clause ::= [who ...] [action ...] last_action
	57	action ::= op [perm ...]
	58	last_action ::= op [perm ...]
	59	who ::= a \| u \| g \| o
	60	op ::= + \| - \| =
	61	perm ::= r \| s \| t \| w \| x \| X \| u \| g \| o
	62
	63	The _\bw_\bh_\bo symbols ``u'', ``g'', and ``o'' specify the user, group, and oth-
	64	er parts of the mode bits, respectively. The _\bw_\bh_\bo symbol ``a'' is equiva-
65	lent to ``ugo''.
66
67	The _\bp_\be_\br_\bm symbols represent the portions of the mode bits as follows:
68
69	r The read bits.
70	s The set-user-ID-on-execution and set-group-ID-on-execution
71	bits.
72	t The sticky bit.
73	w The write bits.
74	x The execute/search bits.
75	X The execute/search bits if the file is a directory or any
76	of the execute/search bits are set in the original (unmodi-
77	fied) mode. Operations with the _\bp_\be_\br_\bm symbol ``X'' are only
78	meaningful in conjunction with the _\bo_\bp symbol ``+'', and are
79	ignored in all other cases.
80	u The user permission bits in the mode of the original file.
81	g The group permission bits in the mode of the original file.
82	o The other permission bits in the mode of the original file.
83
84	The _\bo_\bp symbols represent the operation performed, as follows:
85
86	+ If no value is supplied for _\bp_\be_\br_\bm, the ``+'' operation has no ef-
87	fect. If no value is supplied for _\bw_\bh_\bo, each permission bit speci-
88	fied in _\bp_\be_\br_\bm, for which the corresponding bit in the file mode cre-
89	ation mask is clear, is set. Otherwise, the mode bits represented
90	by the specified _\bw_\bh_\bo and _\bp_\be_\br_\bm values are set.
91
92	- If no value is supplied for _\bp_\be_\br_\bm, the ``-'' operation has no ef-
93	fect. If no value is supplied for _\bw_\bh_\bo, each permission bit speci-
94	fied in _\bp_\be_\br_\bm, for which the corresponding bit in the file mode cre-
95	ation mask is clear, is cleared. Otherwise, the mode bits repre-
96	sented by the specified _\bw_\bh_\bo and _\bp_\be_\br_\bm values are cleared.
97
98	= The mode bits specified by the _\bw_\bh_\bo value are cleared, or, if no who
99	value is specified, the owner, group and other mode bits are
100	cleared. Then, if no value is supplied for _\bw_\bh_\bo, each permission
101	bit specified in _\bp_\be_\br_\bm, for which the corresponding bit in the file
102	mode creation mask is clear, is set. Otherwise, the mode bits rep-
103	resented by the specified _\bw_\bh_\bo and _\bp_\be_\br_\bm values are set.
104
105	Each _\bc_\bl_\ba_\bu_\bs_\be specifies one or more operations to be performed on the mode
106	bits, and each operation is applied to the mode bits in the order speci-
107	fied.
108
109	Operations upon the other permissions only (specified by the symbol ``o''
110	by itself), in combination with the _\bp_\be_\br_\bm symbols ``s'' or ``t'', are ig-
111	nored.
112
113	E\bEX\bXA\bAM\bMP\bPL\bLE\bES\bS
114	644 make a file readable by anyone and writable by the owner
115	only.
116
117	go-w deny write permission to group and others.
118
119	=rw,+X set the read and write permissions to the usual defaults,
120	but retain any execute permissions that are currently set.
121
122	+X make a directory or file searchable/executable by everyone
123	if it is already searchable/executable by anyone.
124
125	755
126	u=rwx,go=rx
127	u=rwx,go=u-w make a file readable/executable by everyone and writable by
128	the owner only.
129
130
131
132	go= clear all mode bits for group and others.
133
134	g=u-w set the group bits equal to the user bits, but clear the
135	group write bit.
136
137	B\bBU\bUG\bGS\bS
138	There's no _\bp_\be_\br_\bm option for the naughty bits.
139
140	S\bSE\bEE\bE A\bAL\bLS\bSO\bO
141	install(1), chmod(2), stat(2), umask(2), fts(3), setmode(3),
142	symlink(7), chown(8)
143
144	S\bST\bTA\bAN\bND\bDA\bAR\bRD\bDS\bS
145	The c\bch\bhm\bmo\bod\bd utility is expected to be POSIX 1003.2 compatible with the ex-
146	ception of the _\bp_\be_\br_\bm symbols ``t'' and ``X'' which are not included in
147	that standard.
148
149	4.4BSD March 31, 1994 3