Transferring control to another program
You can use several different methods to transfer control to another program: static calls, dynamic calls, calls to nested programs, and calls to dynamic link libraries (DLLs).
In addition to making calls between Enterprise COBOL programs, you can also make static and dynamic calls between Enterprise COBOL and programs compiled with older compilers in all environments including CICS®.
For restrictions about making calls with older levels of programs, see Interoperability with older levels of IBM COBOL programs in the Enterprise COBOL for z/OS Migration Guide.
Calling nested programs lets you create applications
using structured programming techniques. You can use nested programs
in place of
PERFORM procedures to prevent unintentional
modification of data items. Call nested programs using either the
CALL literal or
CALL identifier statement.
to dynamic link libraries (DLLs) are an alternative to COBOL dynamic
and are well suited to object-oriented COBOL applications, z/OS® UNIX programs, and applications
that interoperate with C/C++.
Under z/OS, linking two program
objects together results logically in a single program with a
primary entry point and an alternate entry point, each with its own
name. Each name by which a subprogram is to be dynamically called
must be known to the system. You must specify each such name in binder (linkage-editor) control statements as either
NAME or an
ALIAS of the program object that contains the subprogram.
Performance considerations of static and dynamic calls
Making static calls
Making dynamic calls
Making both static and dynamic calls
Calling nested COBOL programs
Enterprise COBOL for z/OS Migration Guide
(Interoperability with older levels of IBM® COBOL programs)