Commands by khashmeshab (4)

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

Check if x509 certificate file and rsa private key match
A x509 certificate and a rsa key file have in common a parameter called modulus, it is a very long hexadecimal number. That value is unique for each certficate / key pair. The command allows to do the check of this pair of values in a script using a great feature of bash. "

Reuse last parameter
Reuse the last parameter of the previous command line

Benchmark SQL Query
Benchmark a SQL query against MySQL Server. The example runs the query 10 times, and you get the average runtime in the output. To ensure that the query does not get cached, use `RESET QUERY CACHE;` on top in the query file.

ffmpeg command that transcodes a MythTV recording for Google Nexus One mobile phone
This command will transcode a MythTV recording. The target device is a Google Nexus One mobile phone. My recordings are from a HDHomerun with Over The Air content. Plays back nicely on the N1.

Change the homepage of Firefox
This command modifies the preferences file of Firefox that is located in .mozilla/firefox/*.default/prefs.js. It edits the file with sed and the -i option. Then it searches the string "browser.startup.homepage", and the string next to it (second string). Finally, it replaces the second string with the new homepage, that is http://sliceoflinux.com in the example. It doesn't work if you haven't set any homepage.

Converts uppercase chars in a string to lowercase
Another alternative is to define a function: lower() { echo ${@,,} } lower StrinG

diff the outputs of two programs
I've been looking for this for a long time. Does anybody know how to do this in dash (POSIX shell)? An alternative version might be: $ exiftool img_1.jpg | diff -

Empty the linux buffer cache

Label EXT2/EXT3 File System

Monitoring file handles used by a particular process
-r : repeat mode


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: