You could start by issuing a directory listing of the files you'd like to copy
ssh user@server "ls -l"
Using that list you can evaluate how many files have been copied (by checking against your local listing) and only request the ones you do not have.
N.B. This will not consider the case where files on the remote server change after they are copied by the client.
L7Sqr
Practically a Posting Shark
849 posts since Feb 2011
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On second thought, why not just use rsync
L7Sqr
Practically a Posting Shark
849 posts since Feb 2011
Reputation Points: 253
Solved Threads: 155
Skill Endorsements: 7