$ rsync -avu --delete sourcedir/ /cygwin/e/destdir/
20 January 2017
This command removes files that have been removed from the source directory but will not overwrite newer files in the destination:
$ rsync -avu --delete sourcedir/ /cygwin/e/destdir/
To rsync to another system with ssh over the net:
$ rsync -avu --delete -e ssh sourcedir/ username@machine:~/destdir/