Commands using grep (1,935)

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands


Check These Out

Scrape commands from commandline fu's 1st page
just bored here at work ... if your are daring ... add '| bash' .... enjoy require 'ruby'

Display ncurses based network monitor
Nload is part of nload package, tested under Debian. Nload display network bandwidth statistics, -u m options stands for MBit unit measure.

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}

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"

test for ksh/bash
Dave Korn gave me this one. It works because ksh allows variable names ( w/o the $name syntax ) used by sh and bash. I wrote it to permit "single source" shell libraries; the current objective: every shell library may be sourced by either shell. see http://github.com/applemcg/backash

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

DVD to YouTube ready watermarked MPEG-4 AVI file using mencoder (step 2)
Reencodes to MPEG-4 DivX output video file from step 1. Audio stream is simply copied. Resizes to 320x240 and deinterlaces as needed. A heading subtitle file is applied as watermark. This heading subtitle file can be a URL.

Get your commandlinefu points (upvotes - downvotes)
This will calculate the your commandlinefu votes (upvotes - downvotes). Hopefully this will boost my commandlinefu points.

Perl One Liner to Generate a Random IP Address

ssh and attach to a screen in one line.
If you know the benefits of screen, then this might come in handy for you. Instead of ssh'ing into a machine and then running a screen command, this can all be done on one line instead. Just have the person on the machine your ssh'ing into run something like $ screen -S debug Then you would run $ ssh -t user@host screen -x debug and be attached to the same screen session.


Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: