Move existing examples into a C++03-specific directory, and add a new

directory for C++11-specific examples. A limited subset of the C++03
examples have been converted to their C++11 equivalents.


[SVN r84312]

example/cpp11/spawn/Jamfile.v2

@@ -0,0 +1,40 @@
+#
+# Copyright (c) 2003-2012 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)
+#
+
+import os ;
+
+if [ os.name ] = SOLARIS
+{
+  lib socket ;
+  lib nsl ;
+}
+else if [ os.name ] = NT
+{
+  lib ws2_32 ;
+  lib mswsock ;
+}
+else if [ os.name ] = HPUX
+{
+  lib ipv6 ;
+}
+
+exe server
+  : echo_server.cpp
+    /boost/context//boost_context
+    /boost/coroutine//boost_coroutine
+    /boost/system//boost_system
+  : <define>BOOST_ALL_NO_LIB=1
+    <threading>multi
+    <os>SOLARIS:<library>socket
+    <os>SOLARIS:<library>nsl
+    <os>NT:<define>_WIN32_WINNT=0x0501
+    <os>NT,<toolset>gcc:<library>ws2_32
+    <os>NT,<toolset>gcc:<library>mswsock
+    <os>NT,<toolset>gcc-cygwin:<define>__USE_W32_SOCKETS
+    <os>HPUX,<toolset>gcc:<define>_XOPEN_SOURCE_EXTENDED
+    <os>HPUX:<library>ipv6
+  ;

example/cpp11/spawn/echo_server.cpp

@@ -0,0 +1,108 @@
+//
+// echo_server.cpp
+// ~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2012 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 <boost/asio/io_service.hpp>
+#include <boost/asio/ip/tcp.hpp>
+#include <boost/asio/spawn.hpp>
+#include <boost/asio/steady_timer.hpp>
+#include <boost/asio/write.hpp>
+#include <iostream>
+#include <memory>
+
+using boost::asio::ip::tcp;
+
+class session : public std::enable_shared_from_this<session>
+{
+public:
+  explicit session(tcp::socket socket)
+    : socket_(std::move(socket)),
+      timer_(socket_.get_io_service()),
+      strand_(socket_.get_io_service())
+  {
+  }
+
+  void go()
+  {
+    auto self(shared_from_this());
+    boost::asio::spawn(strand_,
+        [this, self](boost::asio::yield_context yield)
+        {
+          try
+          {
+            char data[128];
+            for (;;)
+            {
+              timer_.expires_from_now(std::chrono::seconds(10));
+              std::size_t n = socket_.async_read_some(boost::asio::buffer(data), yield);
+              boost::asio::async_write(socket_, boost::asio::buffer(data, n), yield);
+            }
+          }
+          catch (std::exception& e)
+          {
+            socket_.close();
+            timer_.cancel();
+          }
+        });
+
+    boost::asio::spawn(strand_,
+        [this, self](boost::asio::yield_context yield)
+        {
+          while (socket_.is_open())
+          {
+            boost::system::error_code ignored_ec;
+            timer_.async_wait(yield[ignored_ec]);
+            if (timer_.expires_from_now() <= std::chrono::seconds(0))
+              socket_.close();
+          }
+        });
+  }
+
+private:
+  tcp::socket socket_;
+  boost::asio::steady_timer timer_;
+  boost::asio::io_service::strand strand_;
+};
+
+int main(int argc, char* argv[])
+{
+  try
+  {
+    if (argc != 2)
+    {
+      std::cerr << "Usage: echo_server <port>\n";
+      return 1;
+    }
+
+    boost::asio::io_service io_service;
+
+    boost::asio::spawn(io_service,
+        [&](boost::asio::yield_context yield)
+        {
+          tcp::acceptor acceptor(io_service,
+            tcp::endpoint(tcp::v4(), std::atoi(argv[1])));
+
+          for (;;)
+          {
+            boost::system::error_code ec;
+            tcp::socket socket(io_service);
+            acceptor.async_accept(socket, yield[ec]);
+            if (!ec) std::make_shared<session>(std::move(socket))->go();
+          }
+        });
+
+    io_service.run();
+  }
+  catch (std::exception& e)
+  {
+    std::cerr << "Exception: " << e.what() << "\n";
+  }
+
+  return 0;
+}