I am trying to swap the string entered by user

Question

I'm trying to write a bash script to swap the words entered by the user.

For example: hello stack overflow

Output: overflow stack hello

User can enter any number of words.

Answer 1

Take a look at the following article explaining the use of "read" in bash:

http://landoflinux.com/linux_bash_scripting_read.html

If you know ahead of time the number of words you will be switching, a simple solution could be something like this. Each word is assigned to a variable specified in your read command:

#!/bin/bash
echo "Enter two words: "
read one two
echo "first word: $one"
echo "second word: $two"

If you need to reverse a list of words in one string, you can take a look at this answer:

How to reverse a list of words in a shell string?

Answer 2

try this:

read -ra line                        # read into array
i=${#line[@]}                        # determine length of array
for i in $(seq $((i-1)) -1 0); do    # loop in reverse order 
   echo -n "${line[i]} "             # echo entry at i-position without linefeed
done
echo                                 # linefeed

input

this is a test

output

test a is this