All commands (14,187)

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

ssh: change directory while connecting
Useful to create an alias that sends you right in the directory you want : alias server-etc="ssh -t server 'cd /etc && $SHELL'"

Fix borked character coding in a tty.
Often you find some tty programs are messed up and confused about character encoding - 'man' is a common problem and sometimes displays weird characters for apostrophes, hyphens etc etc. Another class of programs that suffer from this are those that try to use the line drawing characters - eg RedHat's tty system admin functions such as system-config-firewall-tui system-config-network-tui etc. Adding 'LC_ALL=C' fixes most of these problems (as long as you want English! Perhaps speakers of other languages can add a comment here). For bonus points, I've added the '-c' option to the man command so that it ignores it's cache and re-computes the man page using the C locale.

which process has a port open

convert uppercase filenames in current directory to lowercase
as commented by Urk...

make a list of movies(.m3u).

Google dictionary of word definitions
$ wget -qO - "http://www.google.com/dictionary/json?callback=dict_api.callbacks.id100&q=steering+wheel&sl=en&tl=en&restrict=pr,de&client=te" this does the actual google dictionary query, returns a JSON string encapsulated in some fancy tag $ sed 's/dict_api\.callbacks.id100.//' here we remove the tag beginning $ sed 's/,200,null)//' and here the tag end There are also some special characters which could cause problems with some JSON parsers, so if you get some errors, this is probably the case (sed is your friend). I laso like to trim the "webDefinitions" part, because it (sometimes) contains misleading information. $ sed 's/\,\"webDefinitions.*//' (but remember to append a "}" at the end, because the JSON string will be invalid) The output also contains links to mp3 files with pronounciation. As of now, this is only usable in the English language. If you choose other than English, you will only get webDefinitions (which are crap).

ionice limits process I/O, to keep it from swamping the system (Linux)
This command is somewhat similar to 'nice', but constrains I/O usage rather than CPU usage. In particular, the '-c3' flag tells the OS to only allow the process to do I/O when nothing else is pending. This dramatically increases the responsiveness of the rest of the system if the process is doing heavy I/O. There's also a '-p' flag, to set the priority of an already-running process.

Ping Twitter to check if you can connect
Returns a JSON object, by connecting to the 'test' endpoint of the Twitter API. Simplest way to check if you can connect to Twitter. Output also available in XML, use '/help/test.xml' for that

find an unused unprivileged TCP port
Some commands (such as netcat) have a port option but how can you know which ports are unused?

show how many regex you use in your vim today
i want to count how many regex code i have used in vim in a long time so i make a directory in svn host and post record to this directory of course i dont want to post manually so i worte a script to do that and this is the core thing to do


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: