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Tree based ps view "painted" by ccze

Compose 2 images to 1
Compose 2 images (foreground.jpg with background.jpg) into 1 (image.jpg), the numeric parameters stablish the size of the foreground.jpg image (96x96) and the position x,y (+250+70) relative to the background.jpg image. Images can be any format, jpg, png, bmp, etc...

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"

Syntax highlight PHP source
Creates HTML code from PHP source

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

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

convert single digit to double digits
each number in a file name gets expanded to the number of digets provided as arg_1 of the arguments in rjust_file_nums. Put the funciton in the .bashrc file. Be sure to $ source ~/.bashrc so that the function will be accessible from bash.

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Check how far along (in %) your program is in a file
Say you're started "xzcat bigdata.xz | complicated-processing-program >summary" an hour ago, and you of course forgot to enable progress output (you could've just put "awk 'NR%1000==0{print NR>"/dev/stderr"}{print}'" in the pipeline but it's too late for that now). But you really want some idea of how far along your program is. Then you can run the above command to see how many % along xzcat is in reading the file. Note that this is for the GNU/Linux version of lsof; the one found on e.g. Darwin has slightly different output so the awk part may need some tweaks.

A simple way to securely use passwords on the command line or in scripts
In this example, where the users gpg keyring has a password, the user will be interactively prompted for the keyring password. If the keyring has no password, same as above, sans the prompt. Suitable for cron jobs. ~/.gnupg/passwd/http-auth.gpg is the encrypted http auth password, for this particular wget use case. This approach has many use cases. example bash functions: function http_auth_pass() { gpg2 --decrypt ~/.gnupg/passwd/http-auth.gpg 2>/dev/null; } function decrypt_pass() { gpg2 --decrypt ~/.gnupg/passwd/"$1" 2>/dev/null; }


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