To invoke the z/OS shell, log on to TSO/E and enter the TSO/E OMVS command. Once you are working in a shell session, you can switch to TSO/E command mode or you can switch to subcommand mode.

Figure 1. Switching temporarily to TSO/E command mode or subcommand mode

To invoke the shell:

1. Log on to TSO/E with your TSO/E user ID and password.
2. At the TSO/E READY prompt, enter the OMVS command. You do not need to supply a password when invoking the shell.

The systems programmer might have set up your TSO/E user's logon to invoke the shell automatically. In that case, you do not need to perform step 2.

You can start multiple shell sessions simultaneously when you log into the shell, and you can start an additional shell session at any time during a shell session by using the OPEN subcommand. You can switch from session to session, using a function key or a subcommand.