Commands by elfreak (4)

  • Escape potential tarbombs

    This Anti-TarBomb function makes it easy to unpack a .tar.gz without worrying about the possibility that it will "explode" in your current directory. I've usually always created a temporary folder in which I extracted the tarball first, but I got tired of having to reorganize the files afterwards. Just add this function to your .zshrc / .bashrc and use it like this; atb arch1.tar.gz and it will create a folder for the extracted files, if they aren't already in a single folder. This only works for .tar.gz, but it's very easy to edit the function to suit your needs, if you want to extract .tgz, .tar.bz2 or just .tar. More info about tarbombs at http://www.linfo.org/tarbomb.html Tested in zsh and bash. UPDATE: This function works for .tar.gz, .tar.bz2, .tgz, .tbz and .tar in zsh (not working in bash): atb() { l=$(tar tf $1); if [ $(echo "$l" | wc -l) -eq $(echo "$l" | grep $(echo "$l" | head -n1) | wc -l) ]; then tar xf $1; else mkdir ${1%.t(ar.gz||ar.bz2||gz||bz||ar)} && tar xf $1 -C ${1%.t(ar.gz||ar.bz2||gz||bz||ar)}; fi ;} UPDATE2: From the comments; bepaald came with a variant that works for .tar.gz, .tar.bz2, .tgz, .tbz and .tar in bash: atb() {shopt -s extglob ; l=$(tar tf $1); if [ $(echo "$l" | wc -l) -eq $(echo "$l" | grep $(echo "$l" | head -n1) | wc -l) ]; then tar xf $1; else mkdir ${1%.t@(ar.gz|ar.bz2|gz|bz|ar)} && tar xf $1 -C ${1%.t@(ar.gz|ar.bz2|gz|bz|ar)}; fi ; shopt -u extglob} Show Sample Output


    10
    atb() { l=$(tar tf $1); if [ $(echo "$l" | wc -l) -eq $(echo "$l" | grep $(echo "$l" | head -n1) | wc -l) ]; then tar xf $1; else mkdir ${1%.tar.gz} && tar xf $1 -C ${1%.tar.gz}; fi ;}
    elfreak · 2010-10-16 05:50:32 5
  • Create an easy to pronounce shortened URL from CLI

    Just add this function to your .zshrc / .bashrc, and by typing "shout *URL*" you get a randomly chosen English word that ShoutKey.com uses to short your URL. You may now go to shoutkey.com/*output_word* and get redirected. The URL will be valid for 5 minutes. (I've never used sed before, so I'll be quite glad if someone could straighten up the sed commands and combine them (perhaps also removing the whitespace). If so, I'll update it right away ;) ) Show Sample Output


    4
    shout () { curl -s "http://shoutkey.com/new?url=$1" | sed -n 's/\<h1\>/\&/p' | sed 's/<[^>]*>//g;/</N;//b' ;}
    elfreak · 2010-10-04 23:50:54 0
  • Stream YouTube URL directly to MPlayer

    A function for streaming youtube to mplayer. The option "-g" for youtube-dl tells it to output the direct video URL, instead of downloading the video. "-fs" tells MPlayer to go FullScreen, and "-quit" makes it less verbose. Requires: youdube-dl ( http://bitbucket.org/rg3/youtube-dl/ ) (Tested in zsh) Show Sample Output


    17
    yt () mplayer -fs -quiet $(youtube-dl -g "$1")
    elfreak · 2010-09-29 18:48:19 11
  • Adding leading zeros to a filename (1.jpg -> 001.jpg)

    From: http://grml.org/zsh/zsh-lovers.html


    8
    zmv '(<1->).jpg' '${(l:3::0:)1}.jpg'
    elfreak · 2010-07-01 14:01:37 0

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Get acurate memory usage of a Process in MegaBytes

Calculate pi with specific scale
a() function in bc is for arctangent, available if using -l option included.

random git-commit message
Do a git commit using a random message.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Clone /
Clone linux installation.

autossh + ssh + screen = super rad perma-sessions
Only useful for really flakey connections (but im stuck with one for now). Though if youre in this situation ive found this to be a good way to run autossh and it does a pretty good job of detecting when the session is down and restarting. Combined with the -t and screen commands this pops you back into your working session lickety split w/ as few headaches as possible. And if autossh is a bit slow at detecting the downed ssh connection, just run this in another tab/terminal window to notify autossh that it should drop it and start over. Basically for when polling is too slow. kill -SIGUSR1 `pgrep autossh`

vi a remote file with port
If you are running sshd on different port use above this command to edit/view remote file with vi/vim. In above example I am using port 12345.

copy public key

Steve Reich - Piano Phase; interpreter: Bourne-Again Shell.
The Piano Phase piece, by Steve Reich is a minimalist composition which is played on two pianos played at slightly different tempos, a task that's very difficult to accomplish by human players. The auditive effects produced by the cell displacement produce beautiful patterns. See https://en.wikipedia.org/wiki/Piano_Phase . My rendered version: https://ydor.org/SteveReich/piano_phase.mp3 Requires sox to be installed on the system. There are multiple videos on youtube showing different approaches and experiences to this interpretation. There is also a synthesized version. Even if Bash can behave as a powerful pianist, a simple threaded version leaves full room to several time glitches and even negative displacements, the same issues that human pianists experience when playing the piece. The older the computer, the better the chaos added to the result due to the CPU load. Apparently that's the reason Steve Reich composes pieces such as this. Without further ado, please give a warm welcome to the Bash minimalist player on synthesized two-threaded pianos. Please turn off your cellphones.

Remove everything except that file
Remove everything except that file with shell tricks inside a subshell to avoid changes in the environment. $ help shopt

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