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RedHat 9 (Linux i386) - man page for chattr (redhat section 1)

CHATTR(1)			     General Commands Manual				CHATTR(1)

NAME
       chattr - change file attributes on a Linux second extended file system

SYNOPSIS
       chattr [ -RV ] [ -v version ] [ mode ] files...

DESCRIPTION
       chattr changes the file attributes on a Linux second extended file system.

       The format of a symbolic mode is +-=[ASacDdIijsTtu].

       The  operator `+' causes the selected attributes to be added to the existing attributes of
       the files; `-' causes them to be removed; and `=' causes them to be  the  only  attributes
       that the files have.

       The  letters `ASacDdijsu' select the new attributes for the files: don't update atime (A),
       synchronous updates (S), synchronous directory updates (D), append  only  (a),  compressed
       (c),  no dump (d), immutable (i), data journalling (j), secure deletion (s), top of direc-
       tory hierarchy (T), no tail-merging (t), and undeletable (u).

OPTIONS
       -R     Recursively change attributes of directories and their  contents.   Symbolic  links
	      encountered during recursive directory traversals are ignored.

       -V     Be verbose with chattr's output and print the program version.

       -v version
	      Set the file's version/generation number.

ATTRIBUTES
       When  a	file  with  the  'A' attribute set is accessed, its atime record is not modified.
       This avoids a certain amount of disk I/O for laptop systems.

       A file with the `a' attribute set can only be open in append mode for writing.	Only  the
       superuser or a process pessessing the CAP_LINUX_IMMUTABLE capability can set or clear this
       attribute.

       A file with the `c' attribute set is automatically compressed on the disk by  the  kernel.
       A  read	from  this  file returns uncompressed data.  A write to this file compresses data
       before storing them on the disk.

       When a directory with the `D' attribute set is modified,  the  changes  are  written  syn-
       chronously on the disk; this is equivalent to the `dirsync' mount option applied to a sub-
       set of the files.

       A file with the `d' attribute set is not candidate for backup when the dump(8) program  is
       run.

       The  'E' attribute is used by the experimental compression patches to indicate that a com-
       pressed file has a compression error.  It  may  not  be	set  or  reset	using  chattr(1),
       although it can be displayed by lsattr(1).

       The 'I' attribute is used by the htree code to indicate that a directory is behind indexed
       using hashed trees.  It may not be set or reset using chattr(1), although it can  be  dis-
       played by lsattr(1).

       A file with the `i' attribute cannot be modified: it cannot be deleted or renamed, no link
       can be created to this file and no data can be written to the file.  Only the superuser or
       a process pessessing the CAP_LINUX_IMMUTABLE capability can set or clear this attribute.

       A file with the `j' attribute has all of its data written to the ext3 journal before being
       written to the file itself, if the  filesystem  is  mounted  with  the  "data=ordered"  or
       "data=writeback"  options.   When  the  filesystem  is  mounted with the "data=journalled"
       option all file data is already journalled and this attribute has  no  effect.	Only  the
       superuser  or  a  process possessing the CAP_SYS_RESOURCE capability can set or clear this
       attribute.

       When a file with the `s' attribute set is deleted, its blocks are zeroed and written  back
       to the disk.

       When  a file with the `S' attribute set is modified, the changes are written synchronously
       on the disk; this is equivalent to the `sync' mount option applied  to  a  subset  of  the
       files.

       A  directory  with the 'T' attribute will be deemed to be the top of directory hierarchies
       for the purposes of the Orlov block allocator (which is used  in  on  systems  with  Linux
       2.5.46 or later).

       A  file	with  the 't' attribute will not have a partial block fragment at the of the file
       merged with other files (for those filesystems which support tail-merging).  This is  nec-
       essary  for  applications  such	as LILO which read the filesystem directly, and who don't
       understand tail-merged files.

       When a file with the `u' attribute set is deleted, its contents are  saved.   This  allows
       the user to ask for its undeletion.

       The  'X'  attribute is used by the experimental compression patches to indicate that a raw
       contents of a compressed file can be accessed directly.	It currently may not  be  set  or
       reset using chattr(1), although it can be displayed by lsattr(1).

       The 'Z' attribute is used by the experimental compression patches to indicate a compressed
       file is dirty.  It may not be set or reset using chattr(1), although it can  be	displayed
       by lsattr(1).

AUTHOR
       chattr was written by Remy Card <Remy.Card@linux.org>.

BUGS AND LIMITATIONS
       As of Linux 2.2, the `c', 's',  and `u' attribute are not honored by the kernel filesystem
       code.	These attributes will be implemented in a future ext2 fs version.

       The `j' option is only useful if the filesystem is mounted as ext3.

       The `D' option is only useful on Linux kernel 2.5.19 and later.

AVAILABILITY
       chattr is part of the e2fsprogs package and  is	available  from  http://e2fsprogs.source-
       forge.net.

SEE ALSO
       lsattr(1)

E2fsprogs version 1.32			  November 2002 				CHATTR(1)


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