Commands by return13 (10)

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Batch resize all images in the current directory that are bigger than 800px, height or weight.
You need to install imagemagick. On Debian type: # apt-get install imagemagick

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"

Enter your ssh password one last time
Enter your ssh public key in the remote end for future key-based authentication. Just type your password one last time. The next time you should be able to login with the public key. If you don't have a key, generate one with ssh-keygen. Requires Bourne-compatible shell in the remote end.

encrypt whole line with ROT13 in vim

one-liner mpc track changer using dmenu
Add a [fluxbox] binding in your key file then this command provides a dmenu selector for the next track to play

dmesg with colored human-readable dates
Use sed to color the output of a human-readable dmesg output

Ergo browsing 'pacman' queries (Arch)
Alternative1 (grep support): pacman -Ss python | paste - - | grep --color=always -e '/python' | less -R Alternative2 (eye-candy, no grep): pacman --color=always -Ss "python" | paste - - | less -R in ~/.bashrc: pkg-grep() { pacman -Ss "$1" | paste - - | grep --color=always -e "${2:-$1}" | less -R ; } pkg-search() { pacman --color=always -Ss "python" | paste - - | less -R; }

Monitor a file with tail with timestamps added
This is useful when watching a log file that does not contain timestamps itself. If the file already has content when starting the command, the first lines will have the "wrong" timestamp when the command was started and not when the lines were originally written.

urldecoding
$ echo "http%3A%2F%2Fwww.google.com" | sed -e's/%\([0-9A-F][0-9A-F]\)/\\\\\x\1/g' | xargs echo -e http://www.google.com $ Works under bash on linux. just alter the '-e' option to its corresponding equivalence in your system to execute escape characters correctly.

Trick find -exec option to execute alias
An alias cannot be executed as command in a find -exec line. This form will trick the command line and let you do the job.


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