ceph/src/boost/libs/asio/example/cpp14/parallel_group/wait_for_one_error.cpp

   1 //
   2 // wait_for_one_error.cpp
   3 // ~~~~~~~~~~~~~~~~~~~~~~
   4 //
   5 // Copyright (c) 2003-2022 Christopher M. Kohlhoff (chris at kohlhoff dot com)
   6 //
   7 // Distributed under the Boost Software License, Version 1.0. (See accompanying
   8 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   9 //
  10
  11 #include <boost/asio.hpp>
  12 #include <boost/asio/experimental/parallel_group.hpp>
  13 #include <iostream>
  14
  15 #if defined(BOOST_ASIO_HAS_POSIX_STREAM_DESCRIPTOR)
  16
  17 int main()
  18 {
  19   boost::asio::io_context ctx;
  20
  21   boost::asio::posix::stream_descriptor in(ctx, ::dup(STDIN_FILENO));
  22   boost::asio::steady_timer timer(ctx, std::chrono::seconds(5));
  23
  24   char data[1024];
  25
  26   boost::asio::experimental::make_parallel_group(
  27       [&](auto token)
  28       {
  29         return in.async_read_some(boost::asio::buffer(data), token);
  30       },
  31       [&](auto token)
  32       {
  33         return timer.async_wait(token);
  34       }
  35     ).async_wait(
  36       boost::asio::experimental::wait_for_one_error(),
  37       [](
  38           std::array<std::size_t, 2> completion_order,
  39           boost::system::error_code ec1, std::size_t n1,
  40           boost::system::error_code ec2
  41       )
  42       {
  43         switch (completion_order[0])
  44         {
  45         case 0:
  46           {
  47             std::cout << "descriptor finished: " << ec1 << ", " << n1 << "\n";
  48           }
  49           break;
  50         case 1:
  51           {
  52             std::cout << "timer finished: " << ec2 << "\n";
  53           }
  54           break;
  55         }
  56       }
  57     );
  58
  59   ctx.run();
  60 }
  61
  62 #else // defined(BOOST_ASIO_HAS_POSIX_STREAM_DESCRIPTOR)
  63 int main() {}
  64 #endif // defined(BOOST_ASIO_HAS_POSIX_STREAM_DESCRIPTOR)