RE: [Boost-users] help: boost::thread and compile error

Guillermo Martony wrote:

Greetings, The following code taken from an example compiles without errors:

#include #include #include <iostream> class thread_alarm { <snip> };

int main() {     int secs = 5;     std::cout << "setting alarm for 5 seconds..." << std::endl;     thread_alarm alarm(secs);     boost::thread thrd(alarm);     thrd.join();     return 0; }

But adding a std::fstream varible to the thread_alarm class: <snip> Results in the following compilation error:

c:\opt\include\boost\function\function_template.hpp(289): error C2664: 'void boost::function0::assign_to(Functor)' : cannot convert parameter 1 from 'const thread_alarm' to 'thread_alarm'         with         [             R=void,             Allocator=int,             Functor=thread_alarm         ]

The boost::thread constructor copies its argument, so the thread_alarm class needs to be copiable, but std::fstream is not copiable. You might be better off using Boost.Bind to produce a lightweight functor.