chattr practice session . I

The following shows a command line session with chattr 
command which helps in changing attributes of files.

$lsattr functions.txt
-------------e-- functions.txt
$chattr -e functions.txt
chattr: Clearing extent flag not supported on functions.txt
$lsattr functions.txt
-------------e-- functions.txt
$chattr +c functions.txt
$lsattr functions.txt
--------c----e-- functions.txt
$lsattr functions.txt
--------c----e-- functions.txt
$chattr +a functions.txt
chattr: Operation not permitted while setting flags on functions.txt
$chattr +C functions.txt
$lsattr functions.txt
--------c----e-- functions.txt
$

The 'e' attribute indicates that the file is using
extents for mapping the blocks on  disk.

A file with the `c' attribute set is automatically 
compressed on the disk by the kernel.

A file with the `a' attribute set can only be open 
in append mode for writing.

A  file  with  the 'C' attribute set will not be subject
to copy-on-write updates.