C++: Threads and Classes

[newntrue]

Hey, I was just curious if you could make a thread out of a class function...if it is possible, what am i doing wrong?

#ifndef USER_H

#define USER_H

#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <iostream>

using std::cout;

class USER {
private:
int *testPTR;
int test;
pthread_t thread1;
char* msg;
int iret1;
protected:
public:
	USER();
	~USER();
	void* run(void *ptr);
	void printTest();
	void start();
};

#endif

USER::USER()
{
	test = 1;
	testPTR = &test;
}

USER::~USER()
{
}

void USER::start()
{
	iret1 = pthread_create(&thread1, NULL, run, (void*) testPTR);
	pthread_join(thread1,NULL);
	return;
}

void* USER::run(void *ptr)
{
	cout<<"thread\n";
	printTest();
}

void USER::printTest()
{
	cout<<"test: "<<test;
	return;
}

[newntrue]

I should probably post the error i'm getting:

$g++ -lpthread test.cpp
user.h: In member function ‘void USER::start()’:
user.h:42: error: argument of type ‘void* (USER::)(void*)’ does not match ‘void* (*)(void*)’

[newntrue]

ok....here's an update on the code....i've taken just a little difference approach...i'm trying to use friend classes... c/o the code

#ifndef USER_H

#define USER_H

#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <iostream>

using std::cout;

class USER {
private:
	int *testPTR;
	int test;
	char* msg;
protected:
public:
	int iret1;
	USER();
	~USER();
	friend void* run(void *ptr);
	void printTest();
	friend void start();
};

#endif

USER::USER()
{
	test = 1;
	testPTR = &test;
}

USER::~USER()
{
}

void start(USER* thisUser)
{
	pthread_t thread1;
	
	thisUser->iret1 = pthread_create(thread1, NULL, run, (void*) thisUser);
	pthread_join(thread1,NULL);
	return;
}

void *run(void *ptr)
{
	USER* thisUser = (USER*) ptr;
	cout<<"thread\n";
	thisUser->printTest();
}

void USER::printTest()
{
	cout<<"test: "<<test;
	return;
}

here is the error that i'm getting now:

$ g++ -lpthread test.cpp
user.h: In function ‘void start(USER*)’:
user.h:43: error: ‘run’ was not declared in this scope

[Dave_Sinkula]

http://www.parashift.com/c++-faq-lit...o-members.html ?

[newntrue]

Hey thanks,
that is a really good site. However I think I followed what his [33.2] said, but i'm still getting an error....

#ifndef USER_H

#define USER_H

#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <iostream>

using std::cout;

class USER {
private:
int *testPTR;
int test;
pthread_t thread1;
char* msg;
int iret1;
protected:
	friend void* accessMemFunc(void* objPtr);
public:
	USER();
	~USER();
	void run();
	void printTest();
	void start();
};

#endif

USER::USER()
{
	test = 1;
	testPTR = &test;
}

USER::~USER()
{
}

void USER::start()
{
	USER* thisUser = this;
	iret1 = pthread_create(&thread1, NULL, accessMemFunc, (void*) thisUser);
	pthread_join(thread1,NULL);
	return;
}

void* accessMemFunc(void* objPtr)
{
	USER* objHandler = (USER*) objPtr;
	objHandler->run();
}

void USER::run()
{
	cout<<"thread\n";
	printTest();
}

void USER::printTest()
{
	cout<<"test: "<<test;
	return;
}

still gets the error:

$ g++ -lpthread test.cpp
user.h: In member function ‘void USER::start()’:
user.h:44: error: ‘accessMemFunc’ was not declared in this scope

btw, my test.cpp script is this:

#include <iostream>
#include "user.h"

int main ()
{
        USER testUser;
        testUser.start();
        return 0;
}

[newntrue]

Maybe if I just discussed what I was trying to do someone could point me in the right direction, because after this i'm guessing that i'm doing it wrong. Ok so, I have this kinda fun idea for a game and wanted it to be shared on a LAN (or internet) which requires a server and a bunch of clients. So how do I get a server to listen to a bunch of clients through sockets? I was gonna try to use a user class for each socket connect (aka user) and inside that user class have a threaded function that just reads info and push out info from the socket connection. I'm kinda new to both sockets and threads (atleast in C++). If it were Java I would have had an easier time. Anyway, can anyone point me to a tutorial or to something helpful. Oh, I think it's also worth noting that I'm on Linux and plan on have the game played on Linux boxes. Thanks in advance!

[l2u]

I would make special class thread that would be base class of each class that wants to run a process and then just make virtual functions.