Method on_transport_error

cpp/src/handler.cpp:49–49

void messaging_handler::on_sendable(sender &) {}
void messaging_handler::on_transport_close(transport &) {}
void messaging_handler::on_transport_error(transport &t) { on_error(t.error()); }
void messaging_handler::on_transport_open(transport &) {}

void messaging_handler::on_connection_close(connection &) {}