Howto | Copy Directories & Preserve Permissions21 Mar 2009
$ cd / $ tar cf - opt | (cd /archive; tar xf - )
You cannot run this command as “sudo”, if you need root access for your copy, then you will need to execute a “sudo su” or log in as root.
What the command will do
With any command that you are given by someone, you should always check what that command will do:
$ tar cf - opt | (cd /archive; tar xf - ) c = create f - = file stdout opt = source path | = pipe all above to... ( cd /archive; x = extract f - = file stdin )
So this command will pipe a new archive from opt to stdout, which it will then recreate in /archive.
This will copy
/archive/opt, preserving permissions, file modification times etc.
Read man tar for more details.