If a file (i.e. hard link) already exists in the backup directory it will be removed. The end result will be that you will be left with a complete mirror of your directory structure at the time of the backup. Due to the use of hard links the amount of disk space used for the backup is minimized.

Note, to create a hard linked backup directory use the script rdup-snapshot which will create it for you. See rdup-snapshot(1) for more information. This only works with GNU cp and GNU date.

Also note that there are no restore utilities, this is because you can copy the backup to another location with the standard unix commands.

-a

Write the uid and gid information to the file's extended user attributes: 'r_uid' and 'r_gid'. This option only works if attr is available on the system. This currently works for Linux and Solaris 10.

-b backupdir

Store the backup in backupdir. This argument is mandatory.

-c

Used in conjunction with rdup's -c. This will allow rdup-snap to be used for remote backups.

-v

Echo the files processed to standard error.

-h

Short help message.

-V

Show the version.