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

remove repeated pairs of characters e.g. "xtxtxtxt" will become "xt"
This will remove repeated characters e.g. echo "xtxtxtxt" | sed -ru 's/(..)\1{2,}/\1/g' the output will just be "xt"

a function to find the fastest DNS server
http://public-dns.info gives a list of online dns servers. you need to change the country in url (br in this url) with your country code. this command need some time to ping all IP in list.

Make Kali Linux look less suspicious by making the desktop look more like a windows machine
To revert back to Kali's original desktop. Just redo the same command with no options .

Find an installed app

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"

Copy a file to a new directory created on the fly
You need to cp, mv, scp, ..., some files around from one place to another, and after having laboriously typed out the source path, you remember that the destination directory doesn't yet exist, and so the command will fail. So rather than killing the command line and starting over, just interpolate the results of creating the directory and echo its name. You could DRY this with a for; do; done, but that may be more trouble than it's worth.

Install pip with Proxy
Installs pip packages defining a proxy

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).

Which .service related this file?
I use this as an alias to get all .service files related a single installed file/conf (if it has services, of course). For rpm based systems ;)

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }


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: