Commands by christoph000 (1)

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

use jq to validate and pretty-print json output
the `jq` tool can also be used do validate json files and pretty print output `cat file.json | jq` available on several platforms, including newer debian-based systems via `#sudo apt install jq`, mac via `brew install jq`, and from source https://stedolan.github.io/jq/download/

Recursive cat - concatenate files (filtered by extension) across multiple subdirectories into one file
Useful if you have to put together multiple files into one and they are scattered across subdirectories. For example: You need to combine all .sql files into one .sql file that would be sent to DBAs as a batch script. You do get a warning if you create a file by the same extension as the ones your searching for. find . -type f -name *.sql -exec cat {} > BatchFile.txt \;

Generate a graph of package dependencies
Requires: imagemagick and graphviz On Debian systems, displays a graph of package dependencies. Works also with other image formats, like svg : $ apt-cache dotty bash | dot -T svg | display

Extend a logical volume to use up all the free space in a volume group

Bytebeat
Never ending music, generated via a C snippet, piped to aplay. Taken from: http://canonical.org/~kragen/bytebeat/

Image to color palette generator
Extract a color palette from a image useful for designers. Example usage: $extract-palette myawesomeimage.jpg 4 Where the first argument is the image you want to extract a palette from. The second argument is the number of colors you want. It may be the case where you want to change the search space. In that case, change the -resize argument to a bigger or smaller result. See the ImageMagick documentation for the -resize argument.

Find files recursively that were updated in the last hour ignoring SVN files and folders.
Find files recursively that were updated in the last hour ignoring SVN files and folders. Incase you do a full svn up on accident.

use vi key bindings at the command line

SVN script for automatically adding and deleting files

Set Time Zone in Ubuntu
Reconfigures time zone in Ubuntu, which I cannot figure out how to do through the GUI. Worked like a charm to set my time zone to CEST from EDT.


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: