// // wait_for_one.cpp // ~~~~~~~~~~~~~~~~ // // Copyright (c) 2003-2021 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 #include int main() { asio::io_context ctx; asio::posix::stream_descriptor in(ctx, ::dup(STDIN_FILENO)); asio::steady_timer timer(ctx, std::chrono::seconds(5)); char data[1024]; asio::experimental::make_parallel_group( [&](auto token) { return in.async_read_some(asio::buffer(data), token); }, [&](auto token) { return timer.async_wait(token); } ).async_wait( asio::experimental::wait_for_one(), []( std::array completion_order, std::error_code ec1, std::size_t n1, std::error_code ec2 ) { switch (completion_order[0]) { case 0: { std::cout << "descriptor finished: " << ec1 << ", " << n1 << "\n"; } break; case 1: { std::cout << "timer finished: " << ec2 << "\n"; } break; } } ); ctx.run(); }