Commands by fromthestone (3)

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Burn CD/DVD from an iso, eject disc when finished.
cdrecord -scanbus will tell you the (x,y,z) value of your cdr (for example, mine is 3,0,0)

Fast portscanner via Parallel

Update dyndns.org with your external IP.
This is great if you are behind a router that does not support dynamic dns updates! Example: AT&T u-verse gateway... Put this in a script and run it as a cron job.

Binary clock
Fun idea! This one adds seconds and keeps running on the same line. Perl's probably cheating though. :)

A DESTRUCTIVE command to render a drive unbootable
Overwrites the boot sector. Since this doesn't overwrite any data, you can usually recover by re-creating the partition table exactly the same as before you zeroed it. This can also help sometimes if you install a new drive in a Windows machine which can't read it.

ARP Scan
A much quicker and (not dirtier) option. use the man page for help. On linux/ubuntu you will need to `sudo apt-get -y install arp-scan`.

GRUB2: set Super Mario as startup tune

Restart openssh-server on your Synology NAS from commandline.
The correct way to restart openssh-server on your synology nas.

a find and replace within text-based files, to locate and rewrite text en mass.
syntax follows regular command line expression. example: let's say you have a directory (with subdirs) that has say 4000 .php files. All of these files were made via script, but uh-oh, there was a typo! if the typo is "let's go jome!" but you meant it to say "let's go home!" find . -name "*.php" | xargs perl -pi -e "s/let\'s\ go\ jome\!/let\'s\ go\ home\!/g" all better :) multiline: find . -name "*.php" | xargs perl -p0777i -e 's/knownline1\nknownline2/replaced/m' indescriminate line replace: find ./ -name '*.php' | xargs perl -pi -e 's/\".*$\"/\new\ line\ content/g'

cd to (or operate on) a file across parallel directories
This is useful for quickly jumping around branches in a file system, or operating on a parellel file. This is tested in bash. cd to (substitute in PWD, a for b) where PWD is the bash environmental variable for the "working directory"

Stay in the loop…

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