MAN page from Other e2fsprogs-1.15-0.i386.rpm

CHATTR

Section: User Commands (1)
Updated: July 1999
Index

NAME

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

SYNOPSIS

chattr[-RV][-vversion][mode]files...

DESCRIPTION

chattrchanges the file attributes on a Linux second extended file system.

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

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

The letters `ASacdisu' select the new attributes for the files: don't update atime (A), synchronous updates (S), append only (a), compressed (c), immutable (i), no dump (d),secure deletion (s), and undeletable (u).

OPTIONS

-R: Recursively change attributes of directories and their contents.Symbolic links encountered during recursive directory traversals areignored.
-V: Be verbose with chattr's output and print the program version.
-v version: Set the files version.

ATTRIBUTES

When a file with the 'A' attribute set is modified, its atime record isnot modified. This avoids a certain amount of disk I/O for laptopsystems.

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.

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

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

A file with the `i' attribute cannot be modified: it cannot be deleted orrenamed, no link can be created to this file and no data can be writtento the file. Only the superuser can set or clear this attribute.

When a file with the `s' attribute set is deleted, its blocks are zeroed andwritten 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 tothe `sync' mount option applied to a subset of the files.

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

AUTHOR

chattrwas written by Remy Card <cardAATTmasi.ibp.fr>, the developer and maintainerof the ext2 fs.

BUGS AND LIMITATIONS

As of ext2 fs 0.5a, the `c' and `u' attribute are not honoured by the kernelcode. As of the Linux 2.0 kernel, the 'A' attribute is not yet supported bythe kernel code. (The noatime code is still in testing.)

These attributes will be implemented in a future ext2 fs version.

AVAILABILITY

chattris part of the e2fsprogs package and is available for anonymous ftp from tsx-11.mit.edu in /pub/linux/packages/ext2fs.

This document was created byman2html,using the manual pages.