我正在查阅asio教程,并尝试运行同步日间客户端和同步日间服务器。我在服务器端调整了代码,将端口号(网站中硬编码的13号端口)改为通过命令行传递。我注意到只有在服务器运行在13号端口时客户端才能连接,但奇怪的是客户端没有显示服务器所在的端口号。
请问这个程序如何知道服务器运行在哪个端口号上,并且只能在13号端口上工作?以下是服务器端的代码:http://www.boost.org/doc/libs/1_45_0/doc/html/boost_asio/tutorial/tutdaytime2/src.html
请问这个程序如何知道服务器运行在哪个端口号上,并且只能在13号端口上工作?以下是服务器端的代码:http://www.boost.org/doc/libs/1_45_0/doc/html/boost_asio/tutorial/tutdaytime2/src.html
//
// client.cpp
// ~~~~~~~~~~
//
// Copyright (c) 2003-2010 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 <iostream>
#include <boost/array.hpp>
#include <boost/asio.hpp>
using boost::asio::ip::tcp;
int main(int argc, char* argv[])
{
try
{
if (argc != 2)
{
std::cerr << "Usage: client <host>" << std::endl;
return 1;
}
boost::asio::io_service io_service;
tcp::resolver resolver(io_service);
tcp::resolver::query query(argv[1], "daytime");
tcp::resolver::iterator endpoint_iterator = resolver.resolve(query);
tcp::resolver::iterator end;
tcp::socket socket(io_service);
boost::system::error_code error = boost::asio::error::host_not_found;
while (error && endpoint_iterator != end)
{
socket.close();
socket.connect(*endpoint_iterator++, error);
}
if (error)
throw boost::system::system_error(error);
for (;;)
{
boost::array<char, 128> buf;
boost::system::error_code error;
size_t len = socket.read_some(boost::asio::buffer(buf), error);
if (error == boost::asio::error::eof)
break; // Connection closed cleanly by peer.
else if (error)
throw boost::system::system_error(error); // Some other error.
std::cout.write(buf.data(), len);
}
}
catch (std::exception& e)
{
std::cerr << e.what() << std::endl;
}
return 0;
}