.B \-RV
]
[
-.B -v
-version
+.B \-v
+.I version
]
[
-mode
+.I mode
]
.I files...
.SH DESCRIPTION
.B chattr
-changes the files attributes on an second extended file system.
+changes the file attributes on a Linux second extended file system.
.PP
-The format of a symbolic mode is +-=[Sacdisu].
+The format of a symbolic mode is +-=[ASacdistu].
.PP
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.
.PP
-The letters `Sacdisu' select the new attributes for the files: synchronous
-updates (S), append only (a), compressed (c), immutable (i), no dump (d),
+The letters `ASacdijsu' select the new attributes for the files:
+don't update atime (A), synchronous updates (S), append only (a),
+compressed (c), no dump (d), immutable (i), data journalling (j),
secure deletion (s), and undeletable (u).
.SH OPTIONS
.TP
-.I -R
+.B \-R
Recursively change attributes of directories and their contents.
+Symbolic links encountered during recursive directory traversals are
+ignored.
.TP
-.I -V
-Verbosely describe changed attributes.
+.B \-V
+Be verbose with chattr's output and print the program version.
.TP
-.I -v version
-Set the files version.
+.BI \-v " version"
+Set the file's version/generation number.
.SH ATTRIBUTES
+When a file with the 'A' attribute set is modified, its atime record is
+not modified. This avoids a certain amount of disk I/O for laptop
+systems.
+.PP
A file with the `a' attribute set can only be open in append mode for writing.
-
+Only the superuser can set or clear this attribute.
+.PP
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.
-
+.PP
A file with the `d' attribute set is not candidate for backup when the
.BR dump (8)
program is run.
-
+.PP
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 can set or clear this attribute.
-
+.PP
+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.
+.PP
When a file with the `s' attribute set is deleted, its blocks are zeroed and
written back to the disk.
-
+.PP
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.
-
-When a file with the `u' attribute set is deleted, its contents is saved.
+.PP
+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 necessary for applications such as LILO
+which read the filesystem directly, and who don't understand tail-merged
+files.
+.PP
+When a file with the `u' attribute set is deleted, its contents are saved.
This allows the user to ask for its undeletion.
+.PP
.SH AUTHOR
.B chattr
-has been written by Remy Card <card@masi.ibp.fr>, the developer and maintainer
-of the ext2 fs.
+was written by Remy Card <Remy.Card@linux.org>.
.SH BUGS AND LIMITATIONS
-As of ext2 fs 0.5a, the `c' and `u' attribute are not honoured by the kernel
-code.
+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.
.PP
-These attributes will be implemented in a future ext2 fs version.
+The `j' option is only useful if the filesystem is mounted as ext3.
.SH AVAILABILITY
.B chattr
-is available for anonymous ftp from ftp.ibp.fr and tsx-11.mit.edu in
-/pub/linux/packages/ext2fs.
+is part of the e2fsprogs package and is available from
+http://e2fsprogs.sourceforge.net.
.SH SEE ALSO
.BR lsattr (1)
git://git.whamcloud.com / tools / e2fsprogs.git / blobdiff