Commands by argherna (3)

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.

Share Your Commands

Check These Out

Create arbitrary big file full of zeroes but done in a second
If you want to create fast a very big file for testing purposes and you do not care about its content, then you can use this command to create a file of arbitrary size within less than a second. Content of file will be all zero bytes. The trick is that the content is just not written to the disk, instead the space for it is somehow reserved on operating system level and file system level. It would be filled when first accessed/written (not sure about the mechanism that lies below, but it makes the file creation super fast). Instead of '1G' as in the example, you could use other modifiers like 200K for kilobytes (1024 bytes), 500M for megabytes (1024 * 1024 bytes), 20G for Gigabytes (1024*1024*1024 bytes), 30T for Terabytes (1024^4 bytes). Also P for Penta, etc... Command tested under Linux.

Search for a string inside all files in the current directory
Searches all files,dirs (also hidden) recursively

Make a zip file with date/time created in the name of the file , zip all sub-directorys
zip -r /tmp/filename-`date +%Y%m%d_%H%M%S`.zip /directory/

enable all bash completions in gentoo
enable each bash completion that you have installed at your system, that's very nice ;)

Finding the fingerprint of a given certificate

Install pip with Proxy
Installs pip packages defining a proxy

Sort all running processes by their memory & CPU usage
you can also pipe it to "tail" command to show 10 most memory using processes.

Match a URL
For the record: I didn't build this. Just shared what I found that worked. Apologies to the original author! I decided I should fix the case where is not matched for the next time I need this. So I read rfc1035 and formalized the host name regex. If anyone finds any more holes, please comment.

Determine space taken by files of certain type
Just how much space are those zillions of database logs taking up ? How much will you gain on a compression rate of say 80% ? This little line gives you a good start for your calculations.

search installed files of package, that doesn't remember his name well. On rpm systems
rpm, sometimes, is not wildcard friendly. To search files installed from package this could be useful. change PACKAGENAME to any package do you want to search

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.


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: