1//
2// ranged_wait_for_all.cpp
3// ~~~~~~~~~~~~~~~~~~~~~~~
4//
5// Copyright (c) 2003-2024 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#include <vector>
15
16#ifdef BOOST_ASIO_HAS_POSIX_STREAM_DESCRIPTOR
17
18int main()
19{
20 boost::asio::io_context ctx;
21
22 boost::asio::posix::stream_descriptor out(ctx, ::dup(STDOUT_FILENO));
23 boost::asio::posix::stream_descriptor err(ctx, ::dup(STDERR_FILENO));
24
25 using op_type = decltype(
26 out.async_write_some(
27 buffers: boost::asio::buffer(data: "", max_size_in_bytes: 0),
28 token: boost::asio::deferred
29 )
30 );
31
32 std::vector<op_type> ops;
33
34 ops.push_back(
35 x: out.async_write_some(
36 buffers: boost::asio::buffer(data: "first\r\n", max_size_in_bytes: 7),
37 token: boost::asio::deferred
38 )
39 );
40
41 ops.push_back(
42 x: err.async_write_some(
43 buffers: boost::asio::buffer(data: "second\r\n", max_size_in_bytes: 8),
44 token: boost::asio::deferred
45 )
46 );
47
48 boost::asio::experimental::make_parallel_group(range&: ops).async_wait(
49 cancellation_condition: boost::asio::experimental::wait_for_all(),
50 token: [](
51 std::vector<std::size_t> completion_order,
52 std::vector<boost::system::error_code> ec,
53 std::vector<std::size_t> n
54 )
55 {
56 for (std::size_t i = 0; i < completion_order.size(); ++i)
57 {
58 std::size_t idx = completion_order[i];
59 std::cout << "operation " << idx << " finished: ";
60 std::cout << ec[idx] << ", " << n[idx] << "\n";
61 }
62 }
63 );
64
65 ctx.run();
66}
67
68#else // defined(BOOST_ASIO_HAS_POSIX_STREAM_DESCRIPTOR)
69int main() {}
70#endif // defined(BOOST_ASIO_HAS_POSIX_STREAM_DESCRIPTOR)
71

source code of boost/libs/asio/example/cpp11/parallel_group/ranged_wait_for_all.cpp