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Preventing buffer overflow when calling functions

tresty (2)
Hello, new to the forum.

I'm pretty much a novice in c++ programming so please bear with me.

Currently I am attempting to control stepper motors from a controlling kit (http://www.pc-control.co.uk/stepperbee_info.htm)

Following the manual, I've written a simple program to run a motor.

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//step.cpp
#include <stdio.h>
#include <stdlib.h>
#include <windows.h>
#include "st.h"


int main()
{
	int status;
	int steps, interval, direction, outputs;

	Type_InitStp InitStp;
	Type_RunMotor1 RunMotor1; 
	Type_StopMotor1 StopMotor1; 
	Type_RunMotor2 RunMotor2; 
	Type_StopMotor2 StopMotor2; 
	Type_SetStepMode SetStepMode; 
	Type_GetCurrentStatus GetCurrentStatus; 

	HINSTANCE HStpDll;

	HStpDll=LoadLibrary("C:\\stp.dll");

	if(HStpDll==NULL)
	{
		abort();
	}
	else
	{
		InitStp=(Type_InitStp)GetProcAddress(HStpDll,"InitStp");
		RunMotor1=(Type_RunMotor1)GetProcAddress(HStpDll,"RunMotor1");
		if(RunMotor1==NULL){abort();}//just to check
		RunMotor2=(Type_RunMotor2)GetProcAddress(HStpDll,"RunMotor2");
		StopMotor1=(Type_StopMotor1)GetProcAddress(HStpDll,"StopMotor1");
		StopMotor2=(Type_StopMotor2)GetProcAddress(HStpDll,"StopMotor2");
		SetStepMode=(Type_SetStepMode)GetProcAddress(HStpDll,"SetStepMode");
		GetCurrentStatus=(Type_GetCurrentStatus)GetProcAddress(HStpDll,"GetCurrentStatus");
	}
		
	status = InitStp();//Manual says 0  is returned if connected
                           //but I get 0 if disconnected and 1 if 
                           //connected so I think there is an error
                           //in the manual.

        steps=100;
	interval=1;
	direction=0;
	outputs=0;

	RunMotor1(steps,interval,direction,outputs);

	return 0;


}

with 

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//st.h (provided by manufacturer)
typedef int	(*Type_InitStp)();
typedef bool	(*Type_RunMotor1)(int steps, int interval, int direction, int outputs);
typedef bool	(*Type_StopMotor1)(int outputs);
typedef bool	(*Type_RunMotor2)(int steps, int interval, int direction, int outputs);
typedef bool	(*Type_StopMotor2)(int outputs);
typedef bool	(*Type_SetStepMode)(int M1Mode, int M2Mode);
typedef bool	(*Type_GetCurrentStatus)(int *M1Active, int *M2Active, int *M1Steps, int *M2Steps,  int *Inputs);


Everything works fine until I call the function RunMotor1 on line 51 where I always get buffer overflow error. I am currently struggling to find a resolution for this.

I've looked around for things like calling conventions (__cdecl, __stdcall) and malloc (new, free), but from what I have tried, the error still pops up.

I would be greatful if anyone could provide me tips in fixing this problem.
Thank you!
helios (17574)
The code looks reasonable to me. You're not doing anything with pointers other than the function pointers, and you're checking RunMotor1, so I see no reason why your code should trigger a buffer overflow. You seem to be following the documentation to the letter, which is a Good Thing, so unless the manual is obviating a critical step, such as some function that needs to be called before RunMotor1(), I see no problem on your side.
Sorry, but other than "keep doing things this way and you'll be generally alright" I have little advice for you. Contact the manufacturer, I guess?
tresty (2)
Thanks for looking through my code helios!

"Contact the manufacturer, I guess?"

I will do so.

Thanks again! :)
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