If you do a lot of downloading via scp and occasionally find yourself restarting a download that failed due to a closed connection, here's an alias that can help. Add the following to your user's ~/.profile file to create a "resumable scp downloading command:
alias scpresume="rsync --partial --progress --rsh=ssh"
This command uses rsync, and sets options for resumable transfers (--partial), displaying a progress bar (--progress), and insures that the transfer will be made using secure shell (-rsh=ssh). To use the command, open a new shell after saving your modified .profile file, and then type scpresume in place of scp in your normal transfer command.
Mac OS X Hints
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