Commands by tejparkash (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

Find the package that installed a command
Put this one-line function somewhere in your shell init, re-login and try $ whatinstalled This is an elaborate wrapper around "dpkg -S", with numerous safeguards. Symlinks and command aliases are resolved. If the searched command is not an existing executable file or was installed by some other means than dpkg/apt, nothing is printed to stdout, otherwise the package name.

Displays the current time using HTTP
This command will show the current GMT time using HTTP. This might be useful if you just want to know what's the current human-readable and accurate-enough time, without changing the system time, using a simple command that would work regardless of the availability of NTP. Note: To get a quicker and more accurate response, replace google.com with your local NTP server. Also can be used as an alternative to the "htpdate" program: http://www.commandlinefu.com/commands/view/668/set-your-computers-clock-using-http-and-htp-http-time-protocol-when-ntpsntp-is-not-available

Remove specific versions of old kernels (Ubuntu/Debian)
If, for example, you want to remove all kernels and headers but the last three versions, you can't use one of that magic all-in-one "remove old stuff" commands. With this simple but elegant command you can remove a range of versions, or a list of versions with e.g. {14,16,20}.

drop first column of output by piping to this
An advantage is that this doesn't modify remained string at all. One can change {0,1} with {0,n} to drop several columns

Ask user to confirm
Returns true if user presses the key. Use it like $ Confirm "Continue" && do action

Extracts PDF pages as images

Go up multiple levels of directories quickly and easily.
This is a kind of wrapper around the shell builtin cd that allows a person to quickly go up several directories. Instead of typing: cd ../.. A user can type: cd ... Instead of: cd ../../.. Type: cd .... Add another period and it goes up four levels. Adding more periods will take you up more levels.

Prints total line count contribution per user for an SVN repository
make usable on OSX with filenames containing spaces. note: will still break if filenames contain newlines... possible, but who does that?!

Slightly better compressed archives
Avoids creating useless directory entries in archive, and sorts files by (roughly) extension, which is likely to group similar files together for better compression. 1%-5% improvement.

Get the serial numbers from HP RAID
This dumps serial numbers of all the drives but HP warranty check does not say they are valid ...


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: