Using an Exec Processing Routine to Invoke an Exec from a Program

To invoke an exec from a high-level language program running in an MVS™ address space, use one of the exec processing routines (IRXEXEC or IRXJCL). If you use IRXEXEC, you must specify parameters that define the exec to be run and supply other related information. For more information, see z/OS TSO/E REXX Reference.

You can also use an exec processing routine to invoke an exec in a TSO/E address space. Two reasons to use them in TSO/E are:

To pass more than one argument to an exec. When invoking an exec implicitly or explicitly, you can pass only one argument string. With IRXEXEC, you can pass multiple arguments.
To call an exec from a program other than a CLIST or exec.