General facts about COBOL to PL/I ILC

A COBOL program cannot be called as a function.
The halfword prefix for PL/I varying strings is exposed, so you need to code the COBOL group data item with a halfword in front of the character string.
PL/I supports access to COBOL files via the COBOL option of the ENVIRONMENT attribute.
See Using storage functions in C to PL/I ILC for information about how to use PL/I's storage facilities with Language Environment storage services.
Language Environment supports the passing of return codes between COBOL and PL/I routines within an ILC application.