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Extract ip addresses with sed
Extracts ip addressess from file using sed. Uses a tag(ip) to grep the IP lines after extracting. Must be a way to just output regex matched on sed.

Save a copy of all debian packages in the form in which they are installed and configured on your system
A copy of all installed debian packages on your system will be put back together, with all changes in configuration files you made and placed in the current directory. Make sure you have enough disk space (say 2-3 GB). Break any time with Ctrl+C.

This will take the last two commands from bash_history and open your editor with the commands on separated lines

See system users

Stat each file in a directory
Possible simplification of egrep-awk-sort with find and -exec with xargs.

determine if tcp port is open
@putnamhill, no need if statement in that case. && is a AND and || is a OR

Print out your hard drive to a jet-direct compatible printer.
Where 192.168.1.2 is a printer with jet-direct. No, I don't suggest this as a backup method.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Delete only binary files in a directory
Please note that binary file checking is NOT perfect. So, use it with caution. It does not delete hidden files whose name has a leading '.' character. And it regards an empty file as a binary file.

Generate a random password 30 characters long
This command is similar to the alternate, except with head(1), you can pick as many passwords as you wish to generate by changing the number of lines you wish to preview.


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