Interprogram Communication
12.5 Communicating with Contained COBOL Programs
Because you cannot specify a Configuration Section for a program contained
within another program, the following types of user-defined words are always
global; that is, they are always accessible from within a contained program:
•
Alphabet-name
•
Class-name
•
Condition-name
•
Mnemonic-name
•
Symbolic-character
These user-defined words can be referenced by statements and entries either in
the program that contains the Configuration Section or any program contained in
that program.
12.6 Calling Compaq COBOL Programs from Other Languages
The CALL and CANCEL verbs allow you to call and cancel Compaq COBOL
programs (including routines and separately compiled program units) from within
a Compaq COBOL program. The
cobcall
,
cobcancel
, and
cobfunc
RTL calls
allow you to call and cancel those programs from programs written in other
languages.
When you use
cobcall
,
cobcancel
, and
cobfunc
, the same considerations and
results will be in effect as if you had used the CALL and CANCEL statements
(see Section 12.1.2 and Section 12.3).
If you need both a CANCEL (to reinitialize data) and a CALL, you can code it
with a single
cobfunc
call.
cobfunc
is essentially a jacket that calls
cobcancel
and
cobcall
.
Table 12–1 shows these calls and their basic differences.
Table 12–1 Calls to COBOL Programs
RTL Call
Function
cobcall
Calls a COBOL program. Program variables remain in their last state.
cobcancel
Cancels a COBOL program. Program variables are reset.
cobfunc
Calls a COBOL program then cancels it. Program variables are reset on
exit.
12.6.1 Calling COBOL Programs from C
Using cobfunc.h as shown in Example 12–8, the C code in Example 12–7
demonstrates a program that calls a COBOL program with three arguments.
In this example the COBOL program, CALLEDFROMC, expects two strings and
an integer.
Example 12–8 could be used as an #include file for the
cobfunc
,
cobcall
, and
cobcancel
functions.
Interprogram Communication 12–19
