Thread and static objects

[axr0284]

Hi,
I have a static function that is the entry point for a thread.

static DWORD WINAPI readPacket(LPVOID thisObject)

thisObject is a pointer to the class where the thread is instantiated.

Since the thread accesses data and functions found in the class, I had to make them static and define them outside of the class.

};
static FILE *filterPacket_logfile; /* The logfile to log errors in*/
static std::string error; /*This is the error printed to the logfile*/
static int (*callback_Function)(unsigned char *, int);

static void writeError(const char *errorString, int init_write);

The problem is that other objects outside of the class now have access to the variables and can modify them.

Is there any way I can have variables that the thread can access but that other objects outside of the class cannot access.

I tried accessing the private data members of the class using thisObject but the compiler says it's an error. The compiler is MS visual Studio .NET 2003.

error C2248: 'filterPacket:ort_Name' : cannot access private member declared in class 'filterPacket'

Thanks a lot for any help,
Amish

[Sebastiani]

you shouldn't have to declare any of the variables as 'static'. just declare the thread entry point within the class with the 'friend' qualifier and it should work.

struct filterPacket
{
	friend
	DWORD 
	WINAPI 
	readPacket(LPVOID thisObject)
	{
		((filterPacket*)thisObject)->port = 80;
	}
	
	private:
	
	unsigned short port;
};

[axr0284]

you shouldn't have to declare any of the variables as 'static'. just declare the thread entry point within the class with the 'friend' qualifier and it should work.

struct filterPacket
{
	friend
	DWORD 
	WINAPI 
	readPacket(LPVOID thisObject)
	{
		((filterPacket*)thisObject)->port = 80;
	}
	
	private:
	
	unsigned short port;
};

That does not quite work. I get the following errors:
error C2255: 'readPacket' : a friend function can only be declared in a class
error C2556: 'void readPacket(LPVOID)' : overloaded function differs only by return type from 'DWORD readPacket(LPVOID)'

with the following code:

riend DWORD WINAPI readPacket(LPVOID thisObject)
{
	int errorCode = 0; /* This is the error code that is returned  */
	filterPacket * filterPacketPtr = (filterPacket*)thisObject;
...

[Sebastiani]

do you have another declaration of readPacket outside of the class?

[axr0284]

Sorry
you were correct. I had the friend modifier in both the declaration and instantiation of the thread. It works now. Thanks a lot,
Amish