Hi everyone, I am a new to boost. When I compile the example of asio_timer, I have a compile error: " g++ -o test_timer test_timer.cpp -I /peter/boost/boost_1_36_0 -lboost_thread-gcc42-mt-1_36 -lboost_system-gcc42-mt-1_36 In file included from /usr/include/c++/4.2/iostream:44, from test_timer.cpp:11: /usr/include/c++/4.2/i486-linux-gnu/bits/c++config.h:149: error: expected constructor, destructor, or type conversion before ‘namespace’ Compilation exited abnormally with code 1 at Tue Oct 28 00:04:58" My compile command is: g++ -o test_timer test_timer.cpp -I /peter/boost/boost_1_36_0 -lboost_thread-gcc42-mt-1_36 -lboost_system-gcc42-mt-1_36 I cannot find the reason. Could you help me? Thanks very much. Best wishes, Wenhao // // time_t_timer.cpp // ~~~~~~~~~~~~~~~~ // // Copyright (c) 2003-2008 Christopher M. Kohlhoff (chris at kohlhoff dot com) // // Distributed under the Boost Software License, Version 1.0. (See accompanying // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) // #include #include <ctime> #include <iostream> struct time_t_traits { // The time type. typedef std::time_t time_type; // The duration type. struct duration_type { duration_type() : value(0) {} duration_type(std::time_t v) : value(v) {} std::time_t value; }; // Get the current time. static time_type now() { return std::time(0); } // Add a duration to a time. static time_type add(const time_type& t, const duration_type& d) { return t + d.value; } // Subtract one time from another. static duration_type subtract(const time_type& t1, const time_type& t2) { return duration_type(t1 - t2); } // Test whether one time is less than another. static bool less_than(const time_type& t1, const time_type& t2) { return t1 < t2; } // Convert to POSIX duration type. static boost::posix_time::time_duration to_posix_duration( const duration_type& d) { return boost::posix_time::seconds(d.value); } }; typedef boost::asio::basic_deadline_timer< std::time_t, time_t_traits> time_t_timer; void handle_timeout(const boost::system::error_code&) { std::cout << "handle_timeout\n"; } int main() { try { boost::asio::io_service io_service; time_t_timer timer(io_service); timer.expires_from_now(5); std::cout << "Starting synchronous wait\n"; timer.wait(); std::cout << "Finished synchronous wait\n"; timer.expires_from_now(5); std::cout << "Starting asynchronous wait\n"; timer.async_wait(handle_timeout); io_service.run(); std::cout << "Finished asynchronous wait\n"; } catch (std::exception& e) { std::cout << "Exception: " << e.what() << "\n"; } return 0; }