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Read a tcpdump file and count SYN packets to port 80, Order column by destination.

Copy input sent to a command to stderr
In the above example 'muspi merol' (the output of the first rev command) is sent to stderr and 'lorem ipsum' (the output of the second rev command) is sent to stdout. rev reverse lines of a file or files. This use of tee allows testing if a program correctly handles its input without using files that hold the data.

JSON processing with Python
Validates and pretty-prints the content fetched from the URL.

Find the package that installed a command

See system users

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"

zsh suffix to inform you about long command ending
make, find and a lot of other programs can take a lot of time. And can do not. Supppose you write a long, complicated command and wonder if it will be done in 3 seconds or 20 minutes. Just add "R" (without quotes) suffix to it and you can do other things: zsh will inform you when you can see the results. You can replace zenity with other X Window dialogs program.

Rename HTML files according to their title tag
The above one-liner could be run against all HTML files in a directory. It renames the HTML files based on the text contained in their title tag. This helped me in a situation where I had a directory containing thousands of HTML documents with meaningless filenames.

Spell check the text in clipboard (paste the corrected clipboard if you like)
xclip -o > /tmp/spell.tmp # Copy clipboard contents to a temp file aspell check /tmp/spell.tmp # Run aspell on that file cat /tmp/spell.tmp | xclip # Copy the results back to the clipboard, so that you can paste the corrected text I'm not sure xclip is installed in most distributions. If not, you can install x11-apps package

Fire CMD every time FILE (or directory) is updated (on *BSD)


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