Read input in shell script

Shell Programming and Scripting
1

I want to write a script that read the input to variable.
I want the input screen to have 2 lines, where the values already input will appear above the input line
for example if I want to input the words below:

like
love
live
life

The screen will display like this:

  1. Before any input
Input words:
  1. after entering
like

:

like 
Input words:
  1. after entering
life

:

like love live life
Input words:

I have tried the following but it keeps giving multiple lines, any ideas?

#!/usr/bin/ksh
n=2
p=""
while [[ $n != "x" ]]
do
    echo "Input words: \c"
    read n
    p=$p" "$n
echo $p
done
2

You'll need man console_codes to position the cursor arbitrarily on the screen, but be aware that not all systems and terminal emulators accept these. Alternatively, try man termcap / terminfo .
You should prefer printf over echo , btw.

3

Hiya

output=""
input=""
while
    echo "$output"
    read input
do output+=" $input"
    # Well this goes forever until you hit CTRL+C
done

hth

4

Thanks you for your effort, but I dont want multiple lines on the screen.

5

OSX 10.7.5, default bash terminal...

#!/bin/bash
n=2
p=""
while [[ $n != "x" ]]
do
    read -p "Input words:- " n
    clear
    p=$p" "$n
    echo "$p "
done

This will print on the top line...

EDIT:
I have just noticed it is calling ksh, apologies chaps...
The bash version works...

6

I dont want my screen to look like this:

Input words: like
like
Input words: love
like love
Input words: live
like love live
Input words: life
like love live life
Input words:

I want it to look like this after :

ike love live life
Input words:
7

I thought you said the bash version worked?

8

Well you been told where to look, and showed how it could work.
Since you love scripts, why dont you try yourself a bit?

I wonder that you state that clear would not work for you...

9

Assuming TERM is set in your environment to correctly indicate your terminal or terminal emulator type, the following should work:

#!/usr/bin/ksh
addword() {
	tput clear
	if [ "$input" != "" ]
	then	if [ "$output" != "" ]
		then	output="$output $input"
		else	output="$input"
		fi
	fi
	printf '%s\nInput words (ctl-d when done): ' "$output"
	read -r input
}
input=
output=
while addword
do	:
done
echo

Although written and tested using ksh , this should work with any POSIX-conforming shell (e.g., ash , bash , dash , ksh , zsh , etc.).

1 Like