Interlanguage Calling Conventions

You should follow these recommendations when writing IBM C and C++ Compilers code to call functions written in other languages:

• Avoid using uppercase letters in identifiers. Fortran and Pascal use only lowercase letters for all external names. Both fold external identifiers to lowercase (by default).
• Avoid using the underscore (_) and dollar sign ($) as the first character in identifiers, to prevent conflict with the naming conventions for the C and C++ language libraries.
• Avoid using long identifier names. The maximum number of significant characters in identifiers is 250 characters.

Corresponding Data Types
Using the Subroutine Linkage Conventions in Interlanguage Calls...
Sample Program: C Calling Fortran