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chmod(1)			 User Commands			      chmod(1)

NAME
       chmod - change the permissions mode of a	file

SYNOPSIS
       chmod [-fR] absolute-mode file...

       chmod [-fR] symbolic-mode-list file...

DESCRIPTION
       The  chmod utility changes or assigns the mode of a file. The mode of a
       file specifies its permissions and other	attributes. The	 mode  may  be
       absolute	or symbolic.

   Absolute mode
       An absolute mode	specification has the following	format:

	      chmod [options] absolute-mode file . . .

       where  absolute-mode  is	 specified using octal numbers nnnn defined as
       follows:

	      n	    a number from 0 to 7. An absolute mode is constructed from
		    the	OR of any of the following modes:

		    4000  Set user ID on execution.

		    20#0  Set group ID on execution if # is 7, 5, 3, or	1.

			  Enable mandatory locking if #	is 6, 4, 2, or 0.

			  For  directories,  files are created with BSD	seman-
			  tics for propagation of the group ID.	With this  op-
			  tion,	files and subdirectories created in the	direc-
			  tory inherit the group ID of the  directory,	rather
			  than	of  the	 current process. For directories, the
			  set-gid bit may only be set or cleared by using sym-
			  bolic	mode.

		    1000  Turn on sticky bit. See chmod(2).

		    0400  Allow	read by	owner.

		    0200  Allow	write by owner.

		    0100  Allow	execute	(search	in directory) by owner.

		    0700  Allow	read, write, and execute (search) by owner.

		    0040  Allow	read by	group.

		    0020  Allow	write by group.

		    0010  Allow	execute	(search	in directory) by group.

		    0070  Allow	read, write, and execute (search) by group.

		    0004  Allow	read by	others.

		    0002  Allow	write by others.

		    0001  Allow	execute	(search	in directory) by others.

		    0007  Allow	read, write, and execute (search) by others.

       For  directories, the setgid bit	cannot be set (or cleared) in absolute
       mode; it	must be	set (or	cleared) in symbolic mode using	g+s (or	g-s).

   Symbolic mode
       A symbolic mode specification has the following format:

	      chmod [options] symbolic-mode-list file .	. .

       where symbolic-mode-list	is a comma-separated list (with	no intervening
       whitespace) of symbolic mode expressions	of the form:

	      [who] operator [permissions]

       Operations  are performed in the	order given. Multiple permissions let-
       ters following a	single operator	cause the corresponding	operations  to
       be performed simultaneously.

       who   zero  or  more  of	the characters u, g, o,	and a specifying whose
	     permissions are to	be changed or assigned:

	     u	   user's permissions

	     g	   group's permissions

	     o	   others' permissions

	     a	   all permissions (user, group, and other)

	     If	who is omitted,	it defaults to a, but the setting of the  file
	     mode  creation mask (see umask in sh(1) or	csh(1) for more	infor-
	     mation) is	taken into account.  When who is omitted,  chmod  will
	     not override the restrictions of your user	mask.

       operator
	     either +, -, or =,	signifying how permissions are to be changed:

	     +	   Add permissions.

		   If permissions is omitted, nothing is added.

		   If  who  is	omitted, add the file mode bits	represented by
		   permissions,	except for the those with  corresponding  bits
		   in the file mode creation mask.

		   If  who  is	present, add the file mode bits	represented by
		   the permissions.

	     -	   Take	away permissions.

		   If permissions is omitted, do nothing.

		   If who is omitted, clear the	file mode bits represented  by
		   permissions,	 except	 for  those with corresponding bits in
		   the file mode creation mask.

		   If who is present, clear the	file mode bits represented  by
		   permissions.

	     =	   Assign permissions absolutely.

		   If  who  is	omitted,  clear	 all file mode bits; if	who is
		   present, clear the file mode	bits represented by who.

		   If permissions is omitted, do nothing else.

		   If who is omitted, add the file mode	 bits  represented  by
		   permissions,	 except	 for the those with corresponding bits
		   in the file mode creation mask.

		   If who is present, add the file mode	 bits  represented  by
		   permissions.

	     Unlike  other  symbolic  operations,  = has an absolute effect in
	     that it resets all	other bits represented by who.	Omitting  per-
	     missions is useful	only with = to take away all permissions.

       permission
	     any compatible combination	of the following letters:

	     l	   mandatory locking

	     r	   read	permission

	     s	   user	or group set-ID

	     t	   sticky bit

	     w	   write permission

	     x	   execute permission

	     X	   execute  permission	if the file is a directory or if there
		   is execute permission for one of the	other user classes

	     u,g,o indicate that permission is to be taken  from  the  current
		   user, group or other	mode respectively.

       Permissions  to	a  file	may vary depending on your user	identification
       number (UID) or group identification number (GID). Permissions are  de-
       scribed in three	sequences each having three characters:

       User		    Group		  Other
       rwx		    rwx			  rwx

       This  example  (user,  group,  and  others all have permission to read,
       write, and execute a given file)	demonstrates two categories for	grant-
       ing permissions:	the access class and the permissions themselves.

       The letter s is only meaningful with u or g, and	t only works with u.

       Mandatory  file	and  record  locking (l) refers	to a file's ability to
       have its	reading	or writing permissions locked while a program  is  ac-
       cessing that file.

       In  a directory which has the set-group-ID bit set (reflected as	either
       -----s--- or -----l--- in the output of 'ls -ld'), files	and  subdirec-
       tories  are created with	the group-ID of	the parent directory--not that
       of current process.

       It is not possible to permit group execution and	enable a  file	to  be
       locked  on  execution at	the same time. In addition, it is not possible
       to turn on the set-group-ID bit and enable a file to be locked on  exe-
       cution at the same time.	The following examples,	therefore, are invalid
       and elicit error	messages:

       chmod g+x,+l file
       chmod g+s,+l file

	     Only the owner of a file or directory  (or	 the  super-user)  may
	     change  that  file's or directory's mode. Only the	super-user may
	     set the sticky bit	on a non-directory file. If you	are not	super-
	     user,  chmod  will	mask the sticky-bit but	will not return	an er-
	     ror. In order to turn on a	 file's	 set-group-ID  bit,  your  own
	     group  ID	must correspond	to the file's and group	execution must
	     be	set.

OPTIONS
       The following options are supported:

       -f    Force. chmod will not complain if it fails	to change the mode  of
	     a file.

       -R    Recursively  descends  through  directory	arguments, setting the
	     mode for each file	as described above. When  symbolic  links  are
	     encountered,  the	mode of	the target file	is changed, but	no re-
	     cursion takes place.

OPERANDS
       The following operands are supported:

       absolute-mode

       symbolic-mode-list
	     Represents	the change to be made to the file mode	bits  of  each
	     file  named  by  one  of the file operands. See Absolute Mode and
	     Symbolic Mode above in the	DESCRIPTION section for	more  informa-
	     tion.

       file  A path name of a file whose file mode bits	are to be modified.

USAGE
       See  largefile(5) for the description of	the behavior of	chmod when en-
       countering files	greater	than or	equal to 2 Gbyte ( 2**31 bytes).

EXAMPLES
       Example 1: Denying execute permission to	everyone

       example%	chmod a-x file

       Example 2: Allowing only	read permission	to everyone

       example%	chmod 444 file

       Example 3: Making a file	readable and writable by the group and others

       example%	chmod go+rw file
       example%	chmod 066 file

       Example 4: Causing a file to be locked during access

       example%	chmod +l file

       Example 5: Allowing everyone to read, write, and	execute	the  file  and
       turn on the set group-ID

       example%	chmod a=rwx,g+s	file
       example%	chmod 2777 file

ENVIRONMENT VARIABLES
       See  environ(5) for descriptions	of the following environment variables
       that affect the execution of chmod: LC_CTYPE, LC_MESSAGES, and NLSPATH.

EXIT STATUS
       The following exit values are returned:

       0     Successful	completion.

       >0    An	error occurred.

ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWcsu			   |
       +-----------------------------+-----------------------------+
       |CSI			     |enabled			   |
       +-----------------------------+-----------------------------+

SEE ALSO
       getfacl(1), ls(1),  setfacl(1),	chmod(2),  attributes(5),  environ(5),
       largefile(5)

NOTES
       Absolute	 changes  do not work for the set-group-ID bit of a directory.
       You must	use g+s	or g-s.

       chmod permits you to produce useless modes so long as they are not  il-
       legal  (for  instance,  making  a text file executable).	chmod does not
       check the file type to see if mandatory locking is meaningful.

       If the filesystem is mounted with the nosuid option,  setuid  execution
       is not allowed.

       If  you	use chmod to change the	file group owner permissions on	a file
       with ACL	entries, both the file group owner  permissions	 and  the  ACL
       mask are	changed	to the new permissions.	Be aware that the new ACL mask
       permissions may change the effective permissions	for  additional	 users
       and groups who have ACL entries on the file. Use	the getfacl(1) command
       to make sure the	appropriate permissions	are set	for all	ACL entries.

SunOS 5.9			  4 Dec	2000			      chmod(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | OPERANDS | USAGE | EXAMPLES | ENVIRONMENT VARIABLES | EXIT STATUS | ATTRIBUTES | SEE ALSO | NOTES

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