Untouch supports the following command line switches which appear
before the directories.
-c or -clear = clear history first and take current file times as the new revert-to point.
-f or -force = revert files back to previous dates whether they have changed or not.
-h or -help = display help on Untouch syntax.
-r or -remove = remove option to remove untouch history i.e. untouch.digest and untouch.log files
-s or -sub or -subdir or -subdirs = process files in subdirectories as well.
-l or -log = create untouch.log files in each directory logging what was done.
-q or -quiet = suppress progress messages.