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complete extraction of a debian-package
extracts the debian-package $debfile to $extractdir, including all packaging-information. to repack the package, just type: $dpkg-deb -b $extractdir

Exclude .svn, .git and other VCS junk for a pristine tarball
~$ tar --version tar (GNU tar) 1.20

live netcat network throughput test
On the another machine write this command. pv -r /dev/zero | nc 192.168.1.1 7777 It will show live throughput between two machine.The destination machine ip is at our example 192.168.1.1 You must multiply by 8 for the network calculation. You must install pv and netcat commands for this commands usage. kerim@bayner.com http://www.bayner.com/

Comparison between the execution output of the last and penultimate command
Useful for checking if there are differences between last and penultimate command.

find previously entered commands (requires configuring .inputrc)
[Click the "show sample output" link to see how to use this keystroke.]   Meta-p is one of my all time most used and most loved features of working at the command line. It's also one that surprisingly few people know about. To use it with bash (actually in any readline application), you'll need to add a couple lines to your .inputrc then have bash reread the .inputrc using the bind command:   $ echo '"\en": history-search-forward' >> ~/.inputrc   $ echo '"\ep": history-search-backward' >> ~/.inputrc   $ bind -f ~/.inputrc     I first learned about this feature in tcsh. When I switched over to bash about fifteen years ago, I had assumed I'd prefer ^R to search in reverse. Intuitively ^R seemed better since you could search for an argument instead of a command. I think that, like using a microkernel for the Hurd, it sounded so obviously right fifteen years ago, but that was only because the older way had benefits we hadn't known about.     I think many of you who use the command line as much as I do know that we can just be thinking about what results we want and our fingers will start typing the commands needed. I assume it's some sort of parallel processing going on with the linguistic part of the brain. Unfortunately, that parallelism doesn't seem to work (at least for me) with searching the history. I realize I can save myself typing using the history shortly after my fingers have already started "speaking". But, when I hit ^R in Bash, everything I've already typed gets ignored and I have to stop and think again about what I was doing. It's a small bump in the road but it can be annoying, especially for long-time command line users. Usually M-p is exactly what I need to save myself time and trouble.     If you use the command line a lot, please give Meta-p a try. You may be surprised how it frees your brain to process more smoothly in parallel. (Or maybe it won't. Post here and let me know either way. ☺)

Counts number of lines (in source code excluding comments)
I took java to make the find command simpler and to state that it works for any language supported by cpp. cpp is the C/C++ preprocessor (interprets macros, removes comments, inserts includes, resolves trigraphs). The -fpreprocessor option tells cpp to assume the input has already been preprocessed so it will only replace comment lines with blank lines. The -L 1 option tells xargs to launch one process for each line, indeed cpp can only process one file at the time...

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" }

Run TOP in Color, split 4 ways for x seconds - the ultimate ps command. Great for init scripts
One of my favorite ways to impress newbies (and old hats) to the power of the shell, is to give them an incredibly colorful and amazing version of the top command that runs once upon login, just like running fortune on login. It's pretty sweet believe me, just add this one-liner to your ~/.bash_profile -- and of course you can set the height to be anything, from 1 line to 1000! $ G=$(stty -g);stty rows $((${LINES:-50}/2));top -n1; stty $G;unset G Doesn't take more than the below toprc file I've added below, and you get all 4 top windows showing output at the same time.. each with a different color scheme, and each showing different info. Each window would normally take up 1/4th of your screen when run like that - TOP is designed as a full screen program. But here's where you might learn something new today on this great site.. By using the stty command to change the terminals internal understanding of the size of your terminal window, you force top to also think that way as well. # save the correct settings to G var. $ G=$(stty -g) # change the number of rows to half the actual amount, or 50 otherwise $ stty rows $((${LINES:-50}/2)) # run top non-interactively for 1 second, the output stays on the screen (half at least) $ top -n1 # reset the terminal back to the correct values, and clean up after yourself $ stty $G;unset G This trick from my [ http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html bash_profile ], though the online version will be updated soon. Just think what else you could run like this! Note 1: I had to edit the toprc file out due to this site can't handle that (uploads/including code). So you can grab it from [ http://www.askapache.com/linux-unix/bash-power-prompt.html my site ] Note 2: I had to come back and edit again because the links weren't being correctly parsed

Show a script or config file without comments or blank lines

Find out which debian package a command (executable) belongs to on debian-based distros
This revision to my command (command #8851) was called for when it failed to find the parent package of 'rlogin', which is really a deep symbolic link to /usr/bin/ssh. This revision fixes this newfound issue, while ensuring fixes of other older issues work too.


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