How to do a script in BASH which takes random text from file? [duplicate]

Question

This question already has an answer here:

• What's an easy way to read random line from a file in Unix command line? 13 answers

I have file like:

aaa

bbb

ccc

ddd

eee

---

And I want to do a script in BASH which can takes random line of this text file, and return it to me as variable or something.

I hear it can be done with some AWK. Any ideas?

UPDATE: I now using this:

shuf -n 1 text.txt

Thanks you all for help!

Answer 1

Please see: read random line

Answer 2

I used a script like this to generate a random line from my singature-quotes file:

#!/bin/bash

QUOTES_FILE=$HOME/.quotes/quotes.txt
numLines=`wc -l $QUOTES_FILE | cut -d" " -f 1`

random=`date +%N`

selectedLineNumber=$(($random - $($random/$numLines) * $numLines + 1))
selectedLine=`head -n $selectedLineNumber $QUOTES_FILE | tail -n 1`

echo -e "$selectedLine"

Answer 3

I would use sed with p argument...

sed -n '43p' 

where 43 could be a variable ...

i don't know much about awk but i guess you could do almost the same thing (however i don't know if awk is turing complete...)

Answer 4

here's a bash way, w/o any external tools

IFS=$'\n'
set -- $(<"myfile")
len=${#@}
rand=$((RANDOM%len+1))
linenum=0
while read -r myline
do
  (( linenum++ ))
  case "$linenum" in
   $rand) echo "$myline";;
  esac
done <"myfile"