Linux in a Nutshell, Third Edition

Name

chattr

Synopsis

chattr [options] mode files

Description

Modify file attributes. Specific to Linux Second Extended Filesystem. Behaves similarly to symbolic chmod, using +, -, and =. mode is in the form opcode attribute. See also lsattr.

Options

-R

Modify directories and their contents recursively.

-V

Print modes of attributes after changing them.

-v version

Set the file’s version.

Opcodes

+

Add attribute.

-

Remove attribute.

=

Assign attributes (removing unspecified attributes).

Attributes

A

Don’t update access time on modify.

a

Append only for writing. Can be set or cleared only by a privileged user.

c

Compressed.

d

No dump.

i

Immutable. Can be set or cleared only by a privileged user.

s

Secure deletion; the contents are zeroed on deletion.

u

Undeletable.

S

Synchronous updates.

Examples

                     chattr +a myfile     
                     As superuser