Commands by Timo (1)

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Add directory to $PATH if it's not already there
Sometimes in a script you want to make sure that a directory is in the path, and add it in if it's not already there. In this example, $dir contains the new directory you want to add to the path if it's not already present. There are multiple ways to do this, but this one is a nice clean shell-internal approach. I based it on http://stackoverflow.com/a/1397020. You can also do it using tr to separate the path into lines and grep -x to look for exact matches, like this: $ if ! $(echo "$PATH" | tr ":" "\n" | grep -qx "$dir") ; then PATH=$PATH:$dir ; fi which I got from http://stackoverflow.com/a/5048977. Or replace the "echo | tr" part with a shell parameter expansion, like $ if ! $(echo "${PATH//:/$'\n'}" | grep -qx "$dir") ; then PATH=$PATH:$dir ; fi which I got from http://www.commandlinefu.com/commands/view/3209/. There are also other more regex-y ways to do it, but I find the ones listed here easiest to follow. Note some of this is specific to the bash shell.

Download an entire website
-p parameter tells wget to include all files, including images. -e robots=off you don't want wget to obey by the robots.txt file -U mozilla as your browsers identity. --random-wait to let wget chose a random number of seconds to wait, avoid get into black list. Other Useful wget Parameters: --limit-rate=20k limits the rate at which it downloads files. -b continues wget after logging out. -o $HOME/wget_log.txt logs the output

Find the package that installed a command

list block devices
Shows all block devices in a tree with descruptions of what they are.

Show GCC-generated optimization commands when using the "-march=native" or "-mtune=native" switches for compilation.
You can tell GCC to automatically select optimization commands and produce optimized code for the local machine (the one compiling the code), but you can't normally see what switches have been selected and used unless you append a "-v" and pause compilation.

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"

Add an audio soundtrack to a series of images to create an flv
Creates a 5 minute flv file, with the given sequence of images and audio with 0.5 fps. The images were created using the following command: for x in `seq 0 300`; do cp ../head.PNG head-`printf '%03d' $x`.png; done You can also inject metadata to seek easier using yamdi as follows: yamdi -i muxed.flv -o video.flv

Get the Volume labels all bitlocker volumes had before being encrypted
Get information of volume labels of bitlocker volumes, even if they are encrypted and locked (no access to filesystem, no password provided). Note that the volume labels can have spaces, but only if you name then before encryption. Renaming a bitlocker partition after being encrypted does not have the same effect as doing it before.

Change pidgin status
Thanks for the comment oshazard, i wasn't aware of purple-remote existence.


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