Hi all. 
Can someone tell me what does the letters -x -f -d mean in command sudo urbackupclientctl add-backupdir -x -f -d /etc ?
In Urnackup site the original command is urbackupclientctl add-backupdir –path.
Thank you for all your help. 
When entering command: sudo urbackupclientctl add-backupdir --help
The screen shows what does that letters mean.
If someone needs this, there is an answer.