Entering cshell from bash

Question

I have a bash script and need to run some commands in cshell inside it.

#!/bin/bash

echo entering_to_cshell
csh
echo in_cshell
exit
echo exited_from_cshell

Why doesn't this script run as expected? It only prints entering_to_cshell and it doesn't exit from cshell.

Answer 1

By using

csh

you start a new subshell where your script isn't executed. That's why none of your following commands are executed. Your script waits for this subshell to end which, as you noted, never happens.

Try

csh -c "echo in_cshell"

This way you don't create a new subshell which isn't impacted by your script.