Unit 9 Research Assignment 1: Exploring How to Call External Programs or Functions from a Program.
When trying to call another external function in another programming language you typically want to try to link the two. With linking different files together generally comes down to subroutine calling conventions. When you make a call to a routine located in another object file, your compiler will have to know what that other object file will name its routine internally, how to pass all its parameters, and what setup and cleanup code the routine will require. All this stuff is generally grouped together under the heading of calling conventions.
For each compiler, it has its own calling conventions, which it likes to use for subroutines. Be aware that I said, "Compiler", not language. The C calling convention in Windows is different than the C calling convention on something such as Linux. So, when you mix languages, you need some way to tell the compiler for either the calling or the called subroutine to use the other language's calling convention for each function. However some platforms, like Windows, have multiple popular calling conventions.
Although, if you have a pair of languages whose compiler writers never thought of each other, then you have no choice but to tell both to use some third convention that they both know about (usually C's). Like for example, to get standard C++, you'd have the server code export its routine functions using the C convention, and tell the client code that the routines it is calling are using the C