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grep compressed log files without extracting
accomplishes the same thing without unzipping the whole file, and while i have never seen a log.tar.gz file that was a binary, i will concede that it might happen, so add the -a in there: $zgrep -ia "string" log.tar.gz it's still shorter/easier to type...

Top ten memory hogs
Inspired by #7065

Look for English words in /dev/urandom
* to get the English dictionary: wget http://www.mavi1.org/web_security/wordlists/webster-dictionary.txt

Multi-thread any command
For instance: $ find . -type f -name '*.wav' -print0 |xargs -0 -P 3 -n 1 flac -V8 will encode all .wav files into FLAC in parallel. Explanation of xargs flags: -P [max-procs]: Max number of invocations to run at once. Set to 0 to run all at once [potentially dangerous re: excessive RAM usage]. -n [max-args]: Max number of arguments from the list to send to each invocation. -0: Stdin is a null-terminated list. I use xargs to build parallel-processing frameworks into my scripts like the one here: http://pastebin.com/1GvcifYa

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" }

Write and read HDD external
Write and read HDD external FreeBSD

Send a local file via email
if "mail -a" fail, try "mutt -a" or "nail -a"

list block devices
Shows all block devices in a tree with descruptions of what they are.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Pull up remote desktop for other than gnome/kde eg fluxbox
If the remote doesn't export its desktop (eg fluxbox, blackbox etc) then you need to run a x11vnc server there and a vncviewer at the local end. This command does the lot for you - it assumes that you can 'ssh' to the box without a password and that x11vnc is installed at the remote end.


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