Using IFS in Bash forloop

While using for loop in Shell scripting, there are times when you want to use filenames or variables with spaces like

$ firewall-cmd --list-rich-rule
rule family="ipv4" source address="192.168.122.1" forward-port port="80" protocol="tcp" to-port="8188"

$ for i in `firewall-cmd --list-rich-rule`; do echo $i ; done

rule
family="ipv4"
source
address="192.168.122.1"
forward-port
port="80"
protocol="tcp"
to-port="8188"

But, you want whole command output in single variable. Then, IFS will come to your help. First, replace IFS environment variable to new line character.

OLDIFS=$IFS
IFS=$"\n"

Notice that we are storing IFS in variable with $"\n". Read more about this here

Now, script looks like this

OLDIFS=$IFS
IFS=$"\n";
for i in `firewall-cmd --list-rich-rule`; do  echo $i ; done
IFS=$OLDIFS

And, you are done.

Output is something like this,

rule family="ipv4" source address="192.168.122.1" forward-port port="80" protocol="tcp" to-port="8188"