Howto Display text files in a shell script

Q. How do I display a text file stored in /tmp directory in a shell script?

A. There are many ways, you can simply use cat command and display back output on screen or read file line by line and display back the output. In some cases you may need to store output to a variable and later display back on screen.

Task: Display output using cat command

Following sample script displays contents of a file called /tmp/input.txt:

#!/bin/bash
FILE="/tmp/input.txt"
echo "*** File - $FILE contents ***"
cat $FILE

Task: Store a file output in a variable

Following sample script displays nameserver IPs:

#!/bin/bash
FILE="/etc/resolv.conf"
OUT=$(awk '{ print $2 }' $FILE)
echo "*** Nameserver IP ***"
for ip in $OUT
do
   echo $ip
done

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