[Error] Visual studio 2017 error LNK2001: unresolved external symbol

[musashi]

Hello guys, I'm trying to compile a simple module following the API_Guide.
That's the code:

// Dll1.cpp : Defines the exported functions for the DLL application.
//

#include "stdafx.h"

//======================
//Module initialisation
//======================
#define ORBITER_MODULE
#include "orbitersdk.h"
HINSTANCE g_hDLL;

DLLCLBK void InitModule(HINSTANCE hModule)
{
	g_hDLL = hModule;
	// perform global module initialisation here
}
DLLCLBK void ExitModule(HINSTANCE hModule)
{
	// perform module cleanup here
}


//======================
//Vessel initialisation
//======================
class MyVessel : public VESSEL2 
{
    public: 
		MyVessel(OBJHANDLE hObj, int fmodel) : VESSEL2(hObj, fmodel) {} 
		~MyVessel() {} 
		// add more vessel methods here 
        void clbkLoadStateEx(FILEHANDLE scn, void *status); 
        void clbkSaveState(FILEHANDLE scn); 
		void clbkSetClassCaps(FILEHANDLE cfg);
    
    private: 
		double myparam;
}; 


void MyVessel::clbkLoadStateEx(FILEHANDLE scn, void *status) 
{
	char *line; while (oapiReadScenario_nextline(scn, line)) 
	{ 
		if (!_strnicmp(line, "MYPARAM", 7)) 
		{ 
			sscanf_s(line + 7, "%lf", &myparam);
		} 
		else 
		{ 
			ParseScenarioLineEx(line, status); 
		} 
	} 
}

void MyVessel::clbkSaveState(FILEHANDLE scn) 
{ 
	VESSEL2::clbkSaveState(scn);
	oapiWriteScenario_float(scn,"MYPARAM", myparam);
}

void MyVessel::clbkSetClassCaps(FILEHANDLE cfg) 
{
	SetEmptyMass(1000.0); 
	SetSize(10.0); 
	//AddMesh(oapiLoadMeshGlobal(“MyVessel.msh”)); 
	// define vessel capabilities here 
}


DLLCLBK VESSEL *ovcInit (OBJHANDLE hvessel, int flightmodel) 
{ 
	return new MyVessel (hvessel, flightmodel); 
}

DLLCLBK void ovcExit(VESSEL *vessel) 
{
	if (vessel) delete (MyVessel*)vessel; 
}

when trying to compile it gives me the following:

Dll1.obj : error LNK2001: unresolved external symbol "__declspec(dllimport) void __cdecl oapiWriteScenario_float(void *,char const *,double)" ([email protected]@[email protected])

Now...I think the reason for that is I have changed in orbiterAPI.h:

OAPIFUNC void oapiWriteScenario_float (FILEHANDLE scn, char *item, double d);

with

OAPIFUNC void oapiWriteScenario_float (FILEHANDLE scn,const char *item, double d);

this because

oapiWriteScenario_float(scn,"MYPARAM", myparam);

gave me an error, marked in red on the code, more specifically:

argument of type "const char*" is incompatible with parameter of type "char*"

same was happening for

#ifdef ORBITER_MODULE
void dummy();
void calldummy () { dummy(); }
DLLCLBK char *ModuleDate () { return __DATE__; }
#endif

with __DATE__ marked in red and which I changed with

#ifdef ORBITER_MODULE
void dummy();
void calldummy () { dummy(); }
DLLCLBK const char *ModuleDate () { return __DATE__; }
#endif

So what do you think should I do? Am I missing something or doing something wrong?
Thanks in advance.

[GLS]

Quote:

Originally Posted by musashi

 Now...I think the reason for that is I have changed in orbiterAPI.h

Hi!
Yeah, you can't change the OrbiterSDK files....
They are your interface to the Orbiter libraries, and those don't change once Martin compiles them. If there are any errors and/or warnings, it's because the user isn't respecting the interface.