Commands by flarn2006 (5)

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.

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Kill all Zombie processes (Guaranteed!)
It identifies the parents of the Zombie processes and kill them. So the new parent of orphan Zombies will be the Init process and he is already waiting for reaping them. Be careful! It may also kill your useful processes just because they are not taking care and waiting for their children (bad parents!).

Backup trought SSH

Send keypresses to an X application
This is a (last resort) way to automate applications that provide no other ways for automation, it would send 'Hello world' to the currently active window. See the manpage (and the -text and -window entries) for how to send special characters and target specific windows. An example: Using xwininfo, I get the id of my XPlanet background window: alanceil@kvirasim:19:51:0:~> xwininfo xwininfo: Please select the window about which you would like information by clicking the mouse in that window. xwininfo: Window id: 0x3600001 "Xplanet 1.2.0" Absolute upper-left X: 0 (..etc..) Now I use xvkbd to tell it to close itself: xvkbd -xsendevent -window 0x3600001 -text "Q" Obviously, the best way is to put these commands in a shellscript - just make sure to include a short sleep (sleep .1 should suffice) after each xvkbd call, or some programs will become confused.

Test I/O performance by timing the writing of 100Mb to disk
Write 200 blocks of 512k to a dummy file with dd, timing the result. The is useful as a quick test to compare the performance of different file systems.

Open files in a split windowed Vim
-o acts like :spit. Use -O (capital o) for side-by-side like :vsplit. Use vim -d or vimdiff if you need a diff(1) comparison. To split gnu Screen instead of vim, use ^A S for horizontal, ^A | for vertical.

create an screenshot, upload it to your server via scp and then open that screenshot in firefox
I often need to send screenshots to other people to explain settings and whatever. So I created this oneline which I use to create the screenshot with imagemagik, upload it via scp to my server and then the command opens an firefox tab with the screenshot. The screenshot can be a region or a window. You just have to replace the parts beginning with YOUR.

find the biggest file in current folder

A bash timer
Starts and shows a timer. banner command is a part of the sysvbanner package. Instead of the banner an echo or figlet commands could be used. Stop the timer with Ctrl-C and elapsed time will be shown as the result.

Indent a one-liner.
Bash builtin type also indents the function.

exclude a column with awk
Here's an awk alternative, for those lacking the version of cut with the --complement argument.

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.


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