cp vs rsync with directories

does cp work with directories?

set up test

    peter@peter:~/tmp/rsynctest$ rm -rf destdir
    peter@peter:~/tmp/rsynctest$ cp -a srcdir destdir
    peter@peter:~/tmp/rsynctest$ rm -rf destdir/dir2/d2f2
    peter@peter:~/tmp/rsynctest$ rm -rf destdir/dir1/d1f1

    peter@peter:~/tmp/rsynctest$ find
    .
    ./destdir
    ./destdir/dir2
    ./destdir/dir2/d2f2
    ./destdir/dir2/d2f1
    ./destdir/dir1
    ./destdir/dir1/d1f1
    ./destdir/dir3
    ./destdir/dir3/d3f1
    ./destdir/dir4
    ./destdir/dir4/dir1
    ./destdir/dir4/dir1/d4d1f1
    ./srcdir
    ./srcdir/dir2
    ./srcdir/dir2/d2f2
    ./srcdir/dir2/d2f1
    ./srcdir/dir1
    ./srcdir/dir1/d1f2
    ./srcdir/dir1/d1f1
    ./srcdir/dir3
    ./srcdir/dir3/d3f1
    ./srcdir/dir3/d3f2
    ./srcdir/dir4
    ./srcdir/dir4/dir1
    ./srcdir/dir4/dir1/d4d1f1

Now we have 2 directories, one with 2 missing files; the goal is to copy only those 2 files.

Try with cp:

    peter@peter:~/tmp/rsynctest$ cp -r srcdir/ destdir/

now we have a "destdir/srcdir" that we don't want

    peter@peter:~/tmp/rsynctest$ find destdir
    destdir
    destdir/dir2
    destdir/dir2/d2f1
    destdir/srcdir
    destdir/srcdir/dir2
    destdir/srcdir/dir2/d2f2
    destdir/srcdir/dir2/d2f1
    destdir/srcdir/dir1
    destdir/srcdir/dir1/d1f2
    destdir/srcdir/dir1/d1f1
    destdir/srcdir/dir3
    destdir/srcdir/dir3/d3f1
    destdir/srcdir/dir3/d3f2
    destdir/srcdir/dir4
    destdir/srcdir/dir4/dir1
    destdir/srcdir/dir4/dir1/d4d1f1
    destdir/dir1
    destdir/dir1/d1f2
    destdir/dir3
    destdir/dir3/d3f1
    destdir/dir3/d3f2
    destdir/dir4
    destdir/dir4/dir1
    destdir/dir4/dir1/d4d1f1

clean up, reset test

    peter@peter:~/tmp/rsynctest$ rm -rf destdir/srcdir/
    peter@peter:~/tmp/rsynctest$ rm -rf destdir/dir2/d2f2
    peter@peter:~/tmp/rsynctest$ rm -rf destdir/dir1/d1f1

Now do it with rsync, which works

    peter@peter:~/tmp/rsynctest$ rsync -a srcdir/ destdir/
    peter@peter:~/tmp/rsynctest$ find destdir
    destdir
    destdir/dir2
    destdir/dir2/d2f2
    destdir/dir2/d2f1
    destdir/dir1
    destdir/dir1/d1f2
    destdir/dir1/d1f1
    destdir/dir3
    destdir/dir3/d3f1
    destdir/dir3/d3f2
    destdir/dir4
    destdir/dir4/dir1
    destdir/dir4/dir1/d4d1f1