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see the partition
Watch a dig in progress
I wanted an easy way to list out the sizes of directories and all of the contents of those directories recursively.
UBNT iwlist command
This works just as well for SMTP. You could run this on your mail server to watch e-mail senders and recipients:
tcpdump -l -s0 -w - tcp dst port 25 | strings | grep -i 'MAIL FROM\|RCPT TO'