How to call a C++ method from C? [duplicate]

Answer 1

You can't just go calling C++ code from C.

You will need to produce a C++ interface that can be called from C.

Something like this

 // interface.h

 #ifdef __cplusplus
 extern "C" {
 #endif

 void createMyclass();

 void callMyclassSendCommandToSerialDevice(int Command, int Parameters, int DeviceId);

 void destroyMyclass();

 #ifdef __cplusplus
 extern }
 #endif

Then you do this:

 static MyClass *myclass;

 void createMyclass()
 {
    try
    {
        myclass = new MyClass;
    }
    catch(...)
    {
       fprintf(stderr, "Uhoh, caught an exception, exiting...\n");
       exit(1);
    }
 }


 void callMyclassSendCommandToSerialDevice(int Command, int Parameters, int DeviceId)
 {
     // May need try/catch here. 
     myclass->sendCommandToSerialDevice(Command, Parameters, DeviceId);
 }

 void destroyMyclass()
 {
    delete myclass;
 }

Note that it's IMPERATIVE that you don't let "exceptions" through the wall to the C code, as that is definite undefined behaviour.