Problem:

Is there a switch which makes COBOL use case dependency for the names of calls within DLLs?  If not, is there a way of specifying that a call should be from a particular DLL?

Resolution:

The CASE directive affects to the symbol that is created by the compiler. But the Micro Focus rts on Windows will search for the symbol in any case, this search is not case sensitive. It is only on Unix that the search is case sensitive.

The best solution is to rename your COBOL function as it is not a good idea to have symbols that match other C symbols.

But if you need to use those names, then the solution is to use LITLINK or call convention 8 for those particular calls. This forces the calls to be resolved at link time.