Boost
C++ Libraries
...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
This is an older version of Boost and was released in 2013. The current version is 1.90.0.
A wait handler must meet the requirements for a handler.
A value h of a wait handler
class should work correctly in the expression h(ec),
where ec is an lvalue of
type const error_code.
A free function as a wait handler:
void wait_handler( const boost::system::error_code& ec) { ... }
A wait handler function object:
struct wait_handler { ... void operator()( const boost::system::error_code& ec) { ... } ... };
A non-static class member function adapted to a wait handler using bind():
void my_class::wait_handler( const boost::system::error_code& ec) { ... } ... socket.async_wait(..., boost::bind(&my_class::wait_handler, this, boost::asio::placeholders::error));