Commands tagged extension (11)

What's this? 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.

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Search inside a folder of jar/zip files
Great for finding which jar some pesky class is hiding in!

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

List all TCP opened ports on localhost in LISTEN mode
Alternative of OJM snippet : This one show the IP too, where ports bind. It's very important, because if there's only instead of, connections from internet are rejected.

Edit video by cutting the part you like without transcoding.
Examples: The following will take frames starting at 15.2 seconds for a total of 45.9 seconds: $ mencoder -ss 15.2 -endpos 30.7 -oac copy -ovc copy mymovie.avi -o myeditedmovie.avi Keep in mind -endpos is the total time, i.e. the output video in this is 3 minutes 3 seconds in length: $ mencoder -ss 1 minute -endpos 2 minutes 3 seconds -oac copy -ovc copy mymovie.avi -o myeditedmovie.avi

RELINK a lot of broken symlinks - FIX broken symlinks after rsync site to new server
After you run this script, you can check status for broken symlink with this command: find -L . -type l

Mapreduce style processing
parallel can be installed on your central node and can be used to run a command multiple times. In this example, multiple ssh connections are used to run commands. (-j is the number of jobs to run at the same time). The result can then be piped to commands to perform the "reduce" stage. (sort then uniq in this example). This example assumes "keyless ssh login" has been set up between the central node and all machines in the cluster. bashreduce may also do what you want.

A signal trap that logs when your script was killed and what other processes were running at that time
trap is the bash builtin that allows you to execute commands when the current script receives a particular signal. Uses $0 for the script name, $$ for the script PID, tee to output to STDOUT as well as a log file and ps to log other running processes.

List by size all of the directories in a given tree.

fuman, an alternative to the 'man' command that shows examples
Example: fuman sed

most used unix commands

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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.


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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,…):

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