In VTAM®, you can use a command verification exit routine (ISTCMMND) to screen and manipulate commands issued by a VTAM operator. (The term operator includes a program operator.) The primary purpose of this installation-wide exit routine is to screen command requests that affect critical nodes in the network.
See the MODIFY EXIT command for information about modifying an installation-wide exit routine. See z/OS Communications Server: SNA Customization for information about the command verification exit routine.