Commands by kjell81d (2)

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Change the window title of your xterm
If you are using an xterm emulation capable terminal emulator, such as PuTTY or xterm on Linux desktop, this command will replace the title of that terminal window. I know it is not nice to have seventeen terminals on your desktop with title PuTTY, you can not tell which one is connected to which server and doing what. Even though the string between the quotes is typed as literals, it needs a little more finesse to make it work. Here is how it is done key-by-key: echo "( ctrl-v then ctrl-[ )0;Enter_Title_String_Here( ctrl-v then ctrl-g )"( enter ) ctrl-v : means hold down ctrl key and hit v at the same time like you are pasting in windoze ; also please don't type the parentheses, i.e., ( and )

Count lines of code across multiple file types, sorted by least amount of code to greatest
The same as the other two alternatives, but now less forking! Instead of using '\;' to mark the end of an -exec command in GNU find, you can simply use '+' and it'll run the command only once with all the files as arguments. This has two benefits over the xargs version: it's easier to read and spaces in the filesnames work automatically (no -print0). [Oh, and there's one less fork, if you care about such things. But, then again, one is equal to zero for sufficiently large values of zero.]

history autocompletion with arrow keys
This will enable the possibility to navigate in the history of the command you type with the arrow keys, example "na" and the arrow will give all command starting by na in the history.You can add these lines to your .bashrc (without &&) to use that in your default terminal.

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"

change dinosaur poop into gold
if firefox is running the database is locked, so you need to copy the places.sqlite file temporarily somewhere to be able to query it...

mean color of an image
You can get the mean value for the colours in an image. Then you can determine, in general, how dark or bright is the image and run some other actions based on that. I'll recommend to readjust the brightness of the images using +sigmoidal-contrast option of imagemagick convert command.

Find the package that installed a command

Extract audio from start to end position from a video
mplayer -vc null -vo null -ao pcm Firefly\ ep\ 10.avi -ss 195 -endpos 246 Will create file audiodump.wav with audio from second 195 to second 246 (the opnening theme).

ssh batch jobs: query hundreds of hosts with an ssh command
Need to query hundreds of hosts with an ssh command ? Of course you'll have setup keys on all your remote HOSTs. But in the case a key is not present this command will skip that node, proceeding on to the next. -t: Force pseudo-tty allocation. This can be used to execute arbitrary screen-based programs on a remote machine. Also prevents unwanted stty messages being sent to console -q: Quiet mode. -o "BatchMode yes" If set to yes, passphrase/password querying will be disabled. This option is useful in scripts and other batch jobs where no user is present

Search for classes in Java JAR files.


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