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Attempt an XSS exploit on commandlinefu.com
Mouse around the title of this item, and note that your cookies are being logged to the console. If I were evil, I could instead send everyone's cookies to my site, and then post up-votes on all my submissions using their cookies, and try to delete every other submission, until clfu was completely pwned by me, redirecting people to malware and porn sites, and so on. Update - now fixed.

Leap year calculation

exec chmod to subfiles
Using `-exec cmd {} +` causes find to build the command using all matching filenames before execution, rather than once per file.

Lock the hardware eject button of the cdrom
This command will lock the hardware eject button of your cdrom drive. Some uses are: 1: If you have a toddler and has discovered the cdrom button 2: If you are carrying a laptop in a bag or case and don't want it to eject if the button is inadvertently pressed. To unlock the button use: $ eject -i 0

Prepend a text to a file.
Prepend text to a file. It doen't need temporary files, ed or sed.

Add temporary <1m entries to old cron
Old cron doesn't allow periods

remove the last of all html files in a directory
sed can be used deleting the last line and with -i option, there's no need to for temp files, the change is made on the actual file

Sync MySQL Servers via secure SSH-tunnel
I wanted to keep a backup of my company database server on my local homeserver. After I found maatkit to sync databases, everything except security seemed fine. SSH takes care of that part.

Efficiently extract lines between markers
GNU Sed can 'address' between two regex, but it continues parsing through to the end of the file. This slight alteration causes it to terminate reading the input file once the STOP match is made. In my example I have included an extra '/START/d' as my 'start' marker line contains the 'stop' string (I'm extracting data between 'resets' and using the time stamp as the 'start'). My previous coding using grep is slightly faster near the end of the file, but overall (extracting all the reset cycles in turn) the new SED method is quicker and a lot neater.

List only executables installed by a debian package
Maybe not clean with big package and too long argument. But return every file who can be executed.


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