The RECEIVE initialization exit (INMRZ01 or INMRZ01R) receives control after the RECEIVE command processor parses the command input line, but before it takes any other action. It receives control once per RECEIVE invocation. You can use the exit to:

• Perform initialization tasks, such as obtaining storage for the exit-to-exit communication word, and opening files.
• Determine if issuers of RECEIVE are allowed to use the command in any form.
• Determine if issuers of RECEIVE who do not have OPERATOR authority are allowed to read files not addressed to their user IDs.