Commands using who (12)

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 usb device
I often use it to find recently added ou removed device, or using find in /dev, or anything similar. Just run the command, plug the device, and wait to see him and only him

Create subversion undo point
Allows you to save progress without committing. To revert to an undo point, svn revert then apply the undo point with patch. $ svn revert -R . && patch -p0 < .undo/2009-03-27_08:08:11rev57 Similar: http://www.commandlinefu.com/commands/view/373/archive-all-files-containing-local-changes-svn

Compare two CSV files, discarding any repeated lines
The value for the sort command's -k argument is the column in the CSV file to sort on. In this example, it sorts on the second column. You must use some form of the sort command in order for uniq to work properly.

Do quick arithmetic on numbers from STDIN with any formatting using a perl one liner.
Good for summing the numbers embedded in text - a food journal entry for example with calories listed per food where you want the total calories. Use this to monitor and keep a total on anything that ouputs numbers.

Anti DDOS
Takes IP from web logs and pipes to iptables, use grep to white list IPs.. use if a particular file is getting requested by many different addresses. Sure, its already down pipe and you bandwidth may suffer but that isnt the concern. This one liner saved me from all the traffic hitting the server a second time, reconfigure your system so your system will work like blog-post-1.php or the similar so legitimate users can continue working while the botnet kills itself.

randomize hostname and mac address, force dhcp renew. (for anonymous networking)
this string of commands will release your dhcp address, change your mac address, generate a new random hostname and then get a new dhcp lease.

Mute xterm
Disable the annoying beep in xterm

output list of modifications for an svn revision
url can be a working copy or url to a svn repository, revision is any valid revision number for that branch.

Given process ID print its environment variables

Submit data to a HTML form with POST method and save the response
Assume that you have a form , in the source look for something similar to : input name="rid" type="TEXT" input name="submit" value="SUBMIT" type="SUBMIT" align="center" Then exec the command to get the response into html More info : www.h3manth.com


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: