Commands using sed

deletes first 55 lines; change the 55 to whatever number

This command converts a MySQL query directly into a .csv (Comma Seperated Value)-file.

So you have a web site and you've plastered your significant other's name all over it. But you broke up with them and have some new love in your life. How do you find all those instances of their name and replace them?

Very useful when the ssh key of a host has changed and ssh refuses to connect to the machine, while giving you the line number that has changed in ~/.ssh/known_hosts.

Just another curl command to get your public facing IP

Original author unknown (I believe off of a wifi hacking forum).

Used in conjuction with ifconfig and cron.. can be handy (especially spoofing AP's)

(relies on 'imagemagick')

This command will convert all .pdf files in a directory into a 800px (wide or height, whichever is smaller) image (with the aspect ratio kept) .jpg.

If the file is named 'example1.pdf' it will be named 'example1.jpg' when it is complete.

This is a VERY worthwhile command! People pay hundreds of dollars for this in the Windows world.

My .jpg files average between 150kB to 300kB, but your's may differ.

Prints a graphical directory tree from your current directory

Use graphicsmagick or imagemagick to composite a RGBA image over a flat white background and discard the alpha channel.

usefull in case of abuser/DoS attacks.

special thanks to XwZ :)

add this alias in .bashrc to fast check the ip address of your modem router

alias myip="curl -s http://myip.dk | grep '' | sed -e 's/]*>//g'"

Uses the PHP binary to check the syntax of all .php files in or below the current working directory. Really handy for doing that last minute check before you commit code to the repository.

Shows the current directory and those below it in a simple tree structure. Recommended use:

alias lt='$command_above'

checking files in current and sub directories, finding out the files containing "sampleString" and removing the containing lines from the file.

* Beware that The command will update the original file [no backup].

The command can be extended if play with 'find' command together,

e.g. it is possible to execute on certain type of files: *.xml, *.txt... (find -name "*.xml" | grep....)

if anybody knows a better solution on that, please drop a comment. thx.

Format a password file for John the Ripper from Cisco configs (Level 5)

Pulled from http://www.openwall.com/lists/john-users/2006/05/14/8

Create a tgz archive of all the files containing local changes relative to a subversion repository.

Add the '-q' option to only include files under version control:

Useful if you are not able to commit yet but want to create a quick backup of your work. Of course if you find yourself needing this it's probably a sign you should be using a branch, patches or distributed version control (git, mercurial, etc..)

Similarly, if you want to print from 10 to the end of line you can use: sed -n '10,$p' filename

This is especially useful if you are dealing with a large file. Sometimes you just want to extract a sample without opening the entire file.

Credit goes to wbx & robert at the comments section of http://www.commandlinefu.com/commands/view/348/get-line1000-from-text.#comment