Shell Programming and Scripting

Hi,

In below code, i am expecting the output has
Bye
Bye

But i am getting has
Bye
Hi

Code:
#!/usr/bin/bash

var="Hi"
cat txt.txt | while read var1
do

next="Bye"
case $var in
Hi)
echo "i am Hi"
var=$next
echo $var
;;
*)
eho "selected option is wrong"
;;
esac

done
echo $var



Pls let me know, whats the problem in my script and why the value which i am assigning inside the case is not reflecting in outside the switch case.


Thanks & Regards,

Try this instead:

Code:

#!/usr/bin/bash

var="Hi"
while read var1
do

next="Bye"
case $var in
Hi)
echo "i am Hi"
var=$next
echo $var
;;
*)
echo "selected option is wrong"
;;
esac

done < txt.txt
echo $var

When a while/read loop is executed in a pipeline it actually runs in a subshell, which means that any variable assignments are invisible to the calling shell.