Linux Commands - Part 1

chmod - this is the command hat we use to change the permission.

 ex:-

chmod 777  test
{change the permission to 777 the file test in the current directory}
chmod 777 /home/melick/test
{change the permission to 777 the file test in the /home/melick directory}
chmod  g-r test {remove read permission in the group}
chmod  g+r test {add read permission in the group}
chmod  o-r test {remove read permission in the other}
chmod  o+r test {add read permission in the other}
chmod  u-r test {remove read permission in the user/owner}
chmod  u+r test {add read permission in the user/owner}
chmod  u=r test {read permission only to the user/owner}
chmod  u=w test {write permission only to the user/owner}

chown - this command is use to change the owner of the file.

chown root test 
  { if we want to change ownership to the file to the root }
-rw-r--r-- 1 root melick 0 2008-12-21 21:11 test
chown Melick:Sachika test
{change 'test' files owner as Melick and group as Sachika}           

chgrp - this command is use to change the group of the file.

chgrp root test     {change the group to 'root' in the file 'test' }