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CHMOD(1)			  Korn Shell			      CHMOD(1)

       chmod - change the access permissions of	files

       chmod [flags] mode file ...

       chmod  changes the permission of	each file according to mode, which can
       be either a symbolic representation of changes to  make,	 or  an	 octal
       number representing the bit pattern for the new permissions.

       Symbolic	 mode  strings	consist	of one or more comma separated list of
       operations that can be performed	on the mode. Each operation is of  the
       form user op perm where user is zero or more of the following letters:

	  u	 User permission bits.

	  g	 Group permission bits.

	  o	 Other permission bits.

	  a	 All  permission  bits.	This is	the default if none are	speci-

       The perm	portion	consists of zero or more of the	following letters:

	  r	 Read permission.

	  s	 Setuid	when u is selected for who and setgid when  g  is  se-
		 lected	for who.

	  w	 Write permission.

	  x	 Execute  permission for files,	search permission for directo-

	  X	 Same as x except that it is ignored for files that do not al-
		 ready have at least one x bit set.

	  l	 Exclusive  lock bit on	systems	that support it. Group execute
		 must be off.

	  t	 Sticky	bit on systems that support it.

       The op portion consists of one or more of the following characters:

	  +	 Cause the permission selected to be  added  to	 the  existing
		 permissions. |	is equivalent to +.

	  -	 Cause	the  permission	selected to be removed to the existing

	  =	 Cause the permission to be set	to the given permissions.

	  &	 Cause the permission selected to be anded with	 the  existing

	  ^	 Cause	the  permission	 selected to be	propagated to more re-
		 strictive groups.

       Symbolic	modes with the user portion omitted are	 subject  to  umask(2)
       settings	unless the = op	or the --ignore-umask option is	specified.

       A  numeric  mode	 is  from  one	to four	octal digits (0-7), derived by
       adding up the bits with values 4, 2, and	1. Any omitted digits are  as-
       sumed  to be leading zeros. The first digit selects the set user	ID (4)
       and set group ID	(2) and	save text image	 (1)  attributes.  The	second
       digit  selects  permissions  for	 the user who owns the file: read (4),
       write (2), and execute (1); the third  selects  permissions  for	 other
       users  in  the  file's  group, with the same values; and	the fourth for
       other users not in the file's group, with the same values.

       For symbolic links, by default, chmod changes the mode on the file ref-
       erenced	by  the	symbolic link, not on the symbolic link	itself.	The -h
       options can be specified	to change the mode of the link.	When  travers-
       ing  directories	 with  -R, chmod either	follows	symbolic links or does
       not follow symbolic links, based	on the options -H, -L, and -P.

       When the	-c or -v options are specified,	change notifications are writ-
       ten  to	standard  output  using	 the format, %s: mode changed to %0.4o
       (%s), with arguments of the pathname, the numeric mode, and the result-
       ing permission bits as would be displayed by the	ls command.

       For  backwards  compatibility,  if an invalid option is given that is a
       valid symbolic mode specification, chmod	treats this as a mode specifi-
       cation rather than as an	option specification.

       This command is not enabled by default. To enable it run	builtin	chmod.

       -H, --metaphysical
	      Follow  symbolic	links  for  command arguments; otherwise don't
	      follow symbolic links when traversing directories.

       -L, --logical, --follow
	      Follow symbolic links when traversing directories.

       -P, --physical, --nofollow
	      Don't follow symbolic links when traversing directories.

       -R, --recursive
	      Change the mode for files	in subdirectories recursively.

       -c, --changes
	      Describe only files whose	permission actually change.

       -f, --quiet, --silent
	      Do not report files whose	permissioins fail to change.

       -h, -l, --symlink
	      Change the mode of symbolic links	on systems that	 support  lch-
	      mod(2). Implies --physical.

       -i, --ignore-umask
	      Ignore  the umask(2) value in symbolic mode expressions. This is
	      probably how you expect chmod to work.

       -n, --show
	      Show actions but do not change any file modes.

       -F file,	--reference=file
	      Omit the mode operand and	use the	mode of	file instead.

       -v, --verbose
	      Describe changed permissions of all files.

       0      All files	changed	successfully.

       >0     Unable to	change mode of one or more files.

       chgrp(1), chown(1), lchmod(1), tw(1), getconf(1), ls(1),	umask(2)

       David J.	Korn, et. al.

       2019, David J. Korn,

				 Oct 03, 2019			      CHMOD(1)


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