I'm trying to pass a member function as the callback in boost::thread.
Given this:

class my_class
{
...
void foo(void);
...
};

Instincts told me to do this:

boost::thread my_thread( std::mem_fun(&my_class::foo) );

You want to use boost::bind for this. The below should work.

my_class *myClassPtr = new my_class;
boost::thread my_thread( boost::bind(&my_class::foo, myClassPtr) );