Command line comparison output

[baterka]

Hi,
is there a way to detect whether there are changes or not in a folder pair via command line?

I'm trying to do a backup of a folder at regular basis conditioned by the fact that the source folder has changed since the last backup execution. The destination folder is affixed by a timestamp so its a completely new copy of the source each time. Since there are not always changes from the last time the backup started, it is not necessary to back it up this time, so I would like to skip the current scheduled backup.

Thank you for any advise. :)