Hi all. I need to maintain a mirror copy (b) of a directory structure (a). The following must take place (assuming the dir structures don't change):

- copy all new files from a to b (/a/1/01/file --> /b/1/01/file
- overwrite copy all changed files a to b
- delete from b files removed from a
- do this for all files in all subdirectories, but ignore (skip) for directories starting with "xyz"

any cli guru's out there willing to share some wisdom?