Commands using echo (1,545)

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Better git diff, word delimited and colorized
I've been using colordiff for years. wdiff is the new fav, except its colors. Word delimited diffs are more interleaved, easing the chore of associating big blocks of changes.

IBM AIX: Extract a .tar.gz archive in one shot

sniff network traffic on a given interface and displays the IP addresses of the machines communicating with the current host (one IP per line)

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Record and share your terminal
It replays plain text terminal screencast from http://shelr.tv/

Limit memory usage per script/program
When I'm testing some scripts or programs, they end up using more memory than anticipated. In that case, computer nearly halts due to swap space usage, and sometimes I have to press Magic SysRq+REISUB to reboot. So, I was looking for a way to limit memory usage per script and found out that ulimit can limit memory. If you run it this way: $ $ ulimit -v 1000000 . $ $ scriptname Then the new memory limit will be valid for that shell. I think changing the limit within a subshell is much more flexible and it won't interfere with your current shell ulimit settings. note: -v 1000000 corresponds to approximately 1GB of RAM

Put public IP address in a variable

Randomize lines in a file
This appends a random number as a first filed of all lines in SOMEFILE then sorts by the first column and finally cuts of the random numbers.

Get your external IP address with a random commandlinefu.com command
There's been so many ways submitted to get your external IP address that I decided we all need a command that will just go pick a random one from the list and run it. This gets a list of "Get your external IP" commands from commanlinefu.com and selects a random one to run. It will run the command and print out which command it used. This is not a serious entry, but it was a learning exercise for me writing it. My personal favourite is "curl icanhazip.com". I really don't think we need any other ways to do this, but if more come you can make use of them with this command ;o). Here's a more useful command that always gets the top voted "External IP" command, but it's not so much fun: $ eval $(curl -s http://www.commandlinefu.com/commands/matching/external/ZXh0ZXJuYWw=/sort-by-votes/plaintext|sed -n '/^# Get your external IP address$/{n;p;q}')

Cryptographically secure 32-bit RNG in strict ZSH
ZSH ships a couple random number generators via the $RANDOM environment variable and rand48() via zsh/mathfunc, but neither are cryptographically secure. This code produces a 32-bit random number suitable for cryptography. It's only dependency is /dev/urandom and it does not rely on any shell commands or 3rd party utilities. It assumes ZSH was compiled with 64-bit integer support.


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