boost:thread - compiler error

Question

I wanted to use boost::thread in my program, but get the following compiler error (Visual Studio 2005):

Error   1   **error C2064**: term does not evaluate t         


        

Answer 1

You are passing a member function to the thread object as the function to call when the thread starts. Since the thread doesn't have the object itself, it can't call the member function. You could make the hello function static, or look at the boost::bind library to send in the object.

Answer 2

Member functions have a this pointer as the first argument. Since there is a boost::thread constructor that accepts function arguments, you don't need to use boost::bind. This will also work:

void HelloWorld::entry()
{
    boost::thread thrd(&HelloWorld::hello,this);
    thrd.join();
}

If your function requires arguments, you can put them after the this pointer argument.

Answer 3

Try it like this - the boost::thread constructor is expecting a boost::function0 (which a function pointer is, but a member function pointer isn't, due to the this pointer).

void HelloWorld::entry()
{
    boost::thread thrd(boost::bind(&HelloWorld::hello,this));
    thrd.join();
}