In ILE, you can write applications in which ILE RPG programs and OPM RPG/400 programs continue to interrelate through the traditional use of dynamic program calls. When using such calls, the calling program specifies the name of the called program on a call statement. The called program's name is resolved to an address at run time, just before the calling program passes control to the called program.
You can also write ILE applications that can interrelate with faster static calls. Static calls involve calls between procedures. A procedure is a self-contained set of code that performs a task and then returns to the caller. An ILE RPG module consists of an optional main procedure followed by zero or more subprocedures. Because the procedure names are resolved at bind time (that is, when you create the program), static calls are faster than dynamic calls.
Static calls also allow
Operational descriptors and omitted parameters can be useful when calling bindable APIs or procedures written in other ILE languages.
For information on running a program refer to Running a Program. For information on program/procedure call, refer to Calling Programs and Procedures.