Passing an Object and getting the return value from a thread call.

[vamsikrishna45]

Hi,
please check my code..

I want to pass a class object into a method of other class through a thread call, I tried but got the error can any one help me on this.please.

struct sample{
int status;
std::vector <std::string> a_row;
size_t column_count;
std::vector <std::string> column;
};
class sess {
private:

public:
int a;
sess(int);
sess();
};
class Gen {
private:
static Gen* gen_obj;
public:
static bool Gen_InstanceFlag;
static Gen* GetInstance();
sample addition(sess);
};

/* End of Header File */

/* Beginning of cpp File */

#include"Class_thread_mixing.h"

bool Gen::Gen_InstanceFlag=false;

Gen* Gen::GetInstance(){
if(!Gen::Gen_InstanceFlag){
Gen::gen_obj = new Gen();
Gen::Gen_InstanceFlag= true;
return gen_obj;
}
else {
return gen_obj;
}
}

sample addition(sess ses_obj){

sample sam;
sam.a_row.push_back("success");
sam.column.push_back("result");
sam.column_count=1;
sam.status=ses_obj.a;

return sam;
}


int main(int argc, char* argv[])
{
HANDLE myhandleA,myhandleB,myhandleC;

Gen* gen=Gen::GetInstance();
sess ses_obj(10);

myhandleA=(HANDLE)_beginthreadex(0, 0, gen->addition(ses_obj),(void*)0, 0, 0);

WaitForSingleObject(myhandleA, INFINITE);

CloseHandle(myhandleA);

getchar();

return 0;
}

This is my code and I am getting an error like "error C2665: '_beginthreadex' : none of the 2 overloads could convert all the argument types"

Can any one suggest me who can I pass the object of sess to a funtion in a thread call and how can I get the results from the thread.

[knn9]

Your arguments to _beginthreadex() are wrong. The 3rd argument should be a pointer to your implementation of the threadproc function:

http://msdn.microsoft.com/en-us/library/windows/desktop/ms686736%28v=vs.85%29.aspx

The 4th argument should be a pointer to the object you want to pass to the threadproc function.

http://msdn.microsoft.com/en-us/library/windows/desktop/ms682453%28v=vs.85%29.aspx

[kbw]

You can't do that. Remember a thread is a separate/parallel unit of execution.

I think you need to pass that session thing as a parameter to something. But I'm not clear on what you're doing.

But first, can you format your code. It's really difficult to read unformatted code.