Commands by swarzynski (10)

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What is my ip?

Force machine to reboot no matter what (even if /sbin/shutdown is hanging)
This will cause your machine to INSTANTLY reboot. No un-mounting of drives or anything. Very handy when something has gone horribly wrong with your server in that co-location facility miles away with no remote hands! Suspect this works with all 2.2, 2.4 and 2.6 Linux kernels compiled with magic-syskey-request support.

urldecoding with one pure BASH builtin
You can use ordinary printf to convert "%23%21%2fbin%2fbash" into "#!/bin/bash" with no external utilities, by using a little known printf feature -- the "%b" specifier converts shell escapes. Replace % with \x and printf will understand the urlencoded string. BASH's printf has an extension to set a variable directly, too. So you get to convert urlencoded strings from garble to plaintext in one step with no externals and no backticks.

Encrypted archive with openssl and tar
The lifehacker way: http://lifehacker.com/software/top/geek-to-live--encrypt-your-data-178005.php#Alternate%20Method:%20OpenSSL "That command will encrypt the unencrypted-data.tar file with the password you choose and output the result to encrypted-data.tar.des3. To unlock the encrypted file, use the following command:" $ openssl des3 -d -salt -in encrypted-data.tar.des3 -out unencrypted-data.tar

search for a file in PATH
Also searches for aliases and shell builtins

check open ports without netstat or lsof

A very quick and slick fork bomb. Handle with care. Don't run on production please...

Rename files in batch

Output files without comments or empty lines
Filter comments and empty lines in files. I find this very useful when trying to find what values are actually set in a very long example config file. I often set an alias for it, like : alias nocomment='grep -v "^\($\|#\)"'

list block devices
Shows all block devices in a tree with descruptions of what they are.


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