Exporting C++ Functions for Use in C-Language Executables

If you have functions in a DLL written in C++ that you want to access from a C-language module, you should declare these functions with C linkage instead of C++ linkage. Unless otherwise specified, the C++ compiler uses C++ type-safe naming (also known as name decoration) and C++ calling conventions, which can be difficult to call from C.

To specify C linkage, specify extern "C" for your function declarations. For example:

extern "C" __declspec( dllexport ) int MyFunc(long parm1);

What do you want to do?

• Export from a DLL using .def files

• Export from a DLL using __declspec(dllexport)

• Export and import using AFX_EXT_CLASS

• Export C functions for use in C or C++-language executables

• Determine which exporting method to use

• Import into an application using __declspec(dllimport)

• Initialize a DLL

What do you want to know more about?

• Decorated names

• Linkage specifications

See Also

Concepts

Exporting from a DLL