Commands by __ (7)

  • Use top to monitor only all processes with the same name fragment 'foo'

    Like command 10870, but no need for sed


    3
    top '-p' $(pgrep -d ' -p ' foo)
    __ · 2012-06-27 18:32:03 3
  • Create a local compressed tarball from remote host directory

    This improves on #9892 by compressing the directory on the remote machine so that the amount of data transferred over the network is much smaller. The command uses ssh(1) to get to a remote host, uses tar(1) to archive and compress a remote directory, prints the result to STDOUT, which is written to a local file. In other words, we are archiving and compressing a remote directory to our local box.


    21
    ssh user@host "tar -zcf - /path/to/dir" > dir.tar.gz
    __ · 2011-12-16 05:48:38 2
  • YouTube Convert and Download All User's Videos to MP3s on the fly

    yt2mp3(){ for j in `seq 1 301`;do i=`curl -s gdata.youtube.com/feeds/api/users/$1/uploads\?start-index=$j\&max-results=1|grep -o "watch[^&]*"`;ffmpeg -i `wget youtube.com/$i -qO-|grep -o 'url_map"[^,]*'|sed -n '1{s_.*|__;s_\\\__g;p}'` -vn -ab 128k "`youtube-dl -e ${i#*=}`.mp3";done;} squeezed the monster (and nifty ☺) command from 7776 from 531 characters to 284 characters, but I don't see a way to get it down to 255. This is definitely a kludge!


    0
    Command in description (Your command is too long - please keep it to less than 255 characters)
    __ · 2011-02-03 08:25:42 1
  • Create QR codes from a URL.

    like 7300, but doesn't clutter your working directory with old qr.*.png files. This will get the QR barcode, and send it right into ImageMagick's 'display' tool. Usage is the same as 7300; just call this function followed by the URL: qrurl http://xkcd.com


    4
    qrurl() { curl -sS "http://chart.apis.google.com/chart?chs=200x200&cht=qr&chld=H|0&chl=$1" -o - | display -filter point -resize 600x600 png:-; }
    __ · 2010-12-16 04:42:05 0
  • Join lines

    awk version of 7210. Slightly longer, but expanding it to catch blank lines is easier: awk 'BEGIN{RS="\0"}{gsub(/\n+/,"<SOMETEXT>");print}' file.txt Show Sample Output


    1
    awk 'BEGIN{RS="\0"}{gsub(/\n/,"<SOMETEXT>");print}' file.txt
    __ · 2010-12-12 21:43:22 0
  • Remove all unused kernels with apt-get

    Note the double space: "...^ii␣␣linux-image-2..." Like 5813, but fixes two bugs: [1]This leaves the meta-packages 'linux-headers-generic' and 'linux-image-generic' alone so that automatic upgrades work correctly in the future. [2]Kernels newer than the currently running one are left alone (this can happen if you didn't reboot after installing a new kernel). I'm bummed that this took 228 characters. I'd like to see a simpler version. Show Sample Output


    7
    aptitude remove $(dpkg -l|awk '/^ii linux-image-2/{print $2}'|sed 's/linux-image-//'|awk -v v=`uname -r` 'v>$0'|sed 's/-generic//'|awk '{printf("linux-headers-%s\nlinux-headers-%s-generic\nlinux-image-%s-generic\n",$0,$0,$0)}')
    __ · 2010-12-11 11:38:15 3
  • Binary clock

    Like 7171, but fixed typo, uses fewer variables, and even more cryptic! Show Sample Output


    4
    read -a A<<<".*.**..*....*** 8 9 5 10 6 0 2 11 7 4";for C in `date +"%H%M"|fold -w1`;do echo "${A:${A[C+1]}:4}";done
    __ · 2010-12-02 22:04:49 1

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Watch the size of a directory using figlet
You can substitute /home/$USER with any path you like.

Get a regular updated list of zombies
to omit "grep -v", put some brackets around a single character

Swap a file or dir with quick resotre
This lets you replace a file or directory and quickly revert if something goes wrong. For example, the current version of a website's files are in public_html. Put a new version of the site in public_html~ and execute the command. The names are swapped. If anything goes wrong, execute it again (up arrow or !!).

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"

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

Make redirects to localhost via /etc/hosts more interesting
Normally when a site is blocked through /etc/hosts, traffic is just being redirected to a non-existent server that isn't going to respond. This helps get your point across a little more clearly than a browser timeout. Of course you could use any number of codes: http://en.wikipedia.org/wiki/List_of_HTTP_status_codes Obviously, this command can be added to init-rc.d, and more sophisticated responses can be given. Seems noteworthy to mention that the information sent from the browser can be parsed using the bash READ builtin (such as 'while read -t 1 statement; do parsing'), and the connection stays open until the script exits. Take care that you must use EXEC:'bash -c foo.sh', as 'execvp' (socat's method for executing scripts) invokes 'sh', not 'bash'.

Python extract json

Give any files that don't already have it group read permission under the current folder (recursive)
Makes any files in the current directory (and any sub-directories) group-readable. Using the "! -perm /g=r" limits the number of files to only those that do not already have this property Using "+" on the end of the -exec body tells find to build the entire command by appending all matching files before execution, so invokes chmod once only, not once per file.

Rename a file with a random name
Give files a random name (don't ask why :-) The function will rename files but maintain their extensions. BUG: If a file doesn't have an extension it will end up with a dot at the end of the name. The parameter '8' for pwgen controls the length of filenames - eight random characters.

New Maintainer for CommandLineFu
Welcome to Jon H. (@fart), the new maintainer of CommandLineFu. . In the absence of a forum, I encourage people welcome him, here, in the comments. . Also... What would you like to improve/change about the site?

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