You can change your shell temporarily by creating a subshell and using that instead of the original shell. You can create a subshell using any shell available on your Unix system. This means that you can look in the /etc/shells file and use a shell listed there, or you can use a shell installed elsewhere on the system (Code Listing 3.6).
Code Listing 3.6. Checking the list of shells from /etc/shells and looking for other programs that end with "sh" is a good way to find all of the shells on the system.
Code Listing 3.7. Type in the shell name (which is really just another Unix command) to change shells.
To find out which temporary shells you can use:
To create a temporary shell (subshell):
To exit a temporary shell (subshell):