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commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

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Open a manpage in the default (graphical) web browser
An easy alias for opening a manpage, nicely HTML formatted, in your set internet browser. If you get a "command exited with status 3" error you need to install groff.

print all except first collumn

Send multiple attachments using mailx
If you're users have ever asked your script to email their reports in separate attachments instead of tar'ring them into one file, then you can use this. You'll need the mailx package of course. In Unix you'd want to add an additional parameter "-m" (uuencode foo.txt foo.txt; uuencode /etc/passwd passwd.txt)|mailx -m -s "Hooosa!" someone@cmdfu.com

get a fresh commandlinefu-item each day as motd
Commandline-fu often has little tricks that I always forget. By adding this to the root-cron (sudo crontab -e) I lean a new trick every day.

Remove comments and empty lines from a conf file
Some conf file are very long (squid.conf) This command help to read it.

most used commands in history (comprehensive)
Most of the "most used commands" approaches does not consider pipes and other complexities. This approach considers pipes, process substitution by backticks or $() and multiple commands separated by ; Perl regular expression breaks up each line using | or < ( or ; or ` or $( and picks the first word (excluding "do" in case of for loops) note: if you are using lots of perl one-liners, the perl commands will be counted as well in this approach, since semicolon is used as a separator

import gpg key from the web
imports a public key from the web. I know this by head.. but useful nevertheless

Convert PNG to GIF
(relies on 'imagemagick') Convert all .png files to .gif. This can also go the other way if you reverse the file extensions in the command, e.g.: $ for file in *.gif; do convert "$file" "$(basename $file .gif).png"; done If the file is named 'example1.png' it will be named 'example1.gif' when it is complete.

A command to post a message and an auto-shortened link to Twitter. The link shortening service is provide by TinyURL.
A command to post a message and an auto-shortened link to Twitter. The link shortening service is provided by TinyURL.

Limit memory usage per script/program
When I'm testing some scripts or programs, they end up using more memory than anticipated. In that case, computer nearly halts due to swap space usage, and sometimes I have to press Magic SysRq+REISUB to reboot. So, I was looking for a way to limit memory usage per script and found out that ulimit can limit memory. If you run it this way: $ $ ulimit -v 1000000 . $ $ scriptname Then the new memory limit will be valid for that shell. I think changing the limit within a subshell is much more flexible and it won't interfere with your current shell ulimit settings. note: -v 1000000 corresponds to approximately 1GB of RAM


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