std::ios_base::event_callback(3)

NAME
std::ios_base::event_callback - std::ios_base::event_callback

Synopsis
   typedef void (*event_callback)(event type, ios_base& ios, int index);
   The type of function callbacks that can be registered using register_callback() to
   be called on specific events.
   type is a value of type ios_base::event which indicates the type of the event that
   will invoke this callback.
   ios refers to the stream object for which the callback is invoked: *this is passed
   as the argument when callbacks are invoked by std::ios_base and std::basic_ios
   member functions.
   index is the user-provided value passed to register_callback() when registering the
   function.

See also
   copyfmt copies formatting information
                     (public member function of std::basic_ios<CharT,Traits>)
   imbue sets locale
                     (public member function)
   destructor destructs the object
   [virtual] (virtual public member function)
   register_callback registers event callback function
                     (public member function)