Commands by santizo (2)

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Cd Deluxe - improved cd command for *nix and windows
Hello, Take a look at this free cd replacement - "cd deluxe" a.k.a. "cdd". It is a free open source (GPLv3) application that I have created. As a long time command line enthusiast I have always been frustrated with the limited capabilities of the humble "cd" command. Especially since that is the most commonly used command line utility! See http://www.plan10.com/cdd for the full details and download information. Thanks, -Mike

Destroy all disks on system simultaneously
This command will use the fdisk utility to find all block devices on your system, and overwrite them with data from the /dev/urandom non-blocking random number generator. CAUTION: This will irrevocably erase EVERY SINGLE physical block storage device visible to the fdisk utility, including plugged USB devices, RAID sets, LVM, etc.

Using netcat to copy files between servers
It bypasses encryption overhead of SSH and depending on configuration can be significantly faster. It's recommended to use only in trusted networks.

Prefix command output with duration for each line
Prefixes each output line with time between it and the previous one.

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)

FizzBuzz in one line of Bash
The (in)famous "FizzBuzz" programming challenge, answered in a single line of Bash code. The "|column" part at the end merely formats the output a bit, so if "column" is not installed on your machine you can simply omit that part. Without "|column", the solution only uses 75 characters. The version below is expanded to multiple lines, with comments added. for i in {1..100} # Use i to loop from "1" to "100", inclusive. do ((i % 3)) && # If i is not divisible by 3... x= || # ...blank out x (yes, "x= " does that). Otherwise,... x=Fizz # ...set x to the string "Fizz". ((i % 5)) || # If i is not divisible by 5, skip (there's no "&&")... x+=Buzz # ...Otherwise, append (not set) the string "Buzz" to x. echo ${x:-$i} # Print x unless it is blanked out. Otherwise, print i. done | column # Wrap output into columns (not part of the test).

Copy your ssh public key to a server from a machine that doesn't have ssh-copy-id
If you use Mac OS X or some other *nix variant that doesn't come with ssh-copy-id, this one-liner will allow you to add your public key to a remote machine so you can subsequently ssh to that machine without a password.

Rename files in batch

Mount a temporary ram partition
For FreeBSD

Create user add lines from partial passwd file
Handy if you are installing a new server or recovering an old one and you have a passwd file with the accounts you want to add to the server. If you edit the file so that only the accounts that you want to add are left this line will spit out the correct useradd lines. The uid, gecos and shell will be preserved.


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