[rdiff-backup-users] restore from backup: can files be deleted again, which didn't exist back in time?

[Marco Moller]

Hello,
I would like to use rdiff-backup to create a system restore point, in order to 
have a backup from which I could recover a previous system state after maybe 
having problems with an "apt-get upgrade" or my own stupid system changes. I 
understand how the incremental backup will be done, and how I could recover to 
any older state of a file, or restoring a file which meanwhile became lost in 
my computer. But I do not understand from the documentation how rdiff-backup 
treats the situation in which a file did not exist back in time and a system 
restoration is requested for rebuilding my system state as it was back in time.

1) Will rdiff-backup recognize that a meanwhile present file wasn't present 
back in time and thus delete the meanwhile present file, so that the restore 
does not just merge the files from the backup with the present files?

2) Just for curiosity, if rdiff-backup would take care of the "not only merge" 
situation and would properly delete the newly appeared files again, where does 
rdiff-backup store the information about the files which maybe would have to be 
deleted?

Thanks a lot in advance! The proper answer could also be added to the 
rdiff-backup documentation, by the way.
Talby.