At least 2-3 times a year I come across a very useful linux
command line tool that I think to myself… "How did I not know about this
tool, it's so useful!"
This is command 'shuf'
is one of those tools.
The need
I was writing a simple bash script last night to simply use
curl to test out a restful service I am working on. It’s a restful service that accepts a POST
of a JSON file. I wanted some of the
number values in the JSON post to be randomized, something like 12.34 22.14
some floaty looking number within a narrow range.
Doing a quick google search I came across the command line
tool shuf.
Here are some basic examples of what it can do.
Will generate a list of the integers 10 to 20 inclusive and
shuffle them up.
Or for my purposes I just wanted 1 number
Does the same thing but returns you a number in the shuffled list
Returns 3 numbers
For my base script I wanted to create a random number like
12.21 (it was not important that it be
really random)
|
#!/bin/bash
for ((i = 0; i <
20; i++))
do
num=`shuf -i 1-20 -n 1`.`shuf -i 1-99 -n
1`
echo $num
done
|
Here are the results of the program running.
[1] shuf(1) - Linux man page
Accessed
03/2013
[2] shuf — generate random
permutations
Accessed 03/2013
