#include <boost/asio.hpp>
#include <boost/asio/experimental/parallel_group.hpp>
#include <iostream>
#include <vector>
#ifdef BOOST_ASIO_HAS_POSIX_STREAM_DESCRIPTOR
int main()
{
boost::asio::io_context ctx;
boost::asio::posix::stream_descriptor out(ctx, ::dup(STDOUT_FILENO));
boost::asio::posix::stream_descriptor err(ctx, ::dup(STDERR_FILENO));
using op_type = decltype(
out.async_write_some(boost::asio::buffer("", 0))
);
std::vector<op_type> ops;
ops.push_back(
out.async_write_some(boost::asio::buffer("first\r\n", 7))
);
ops.push_back(
err.async_write_some(boost::asio::buffer("second\r\n", 8))
);
boost::asio::experimental::make_parallel_group(ops).async_wait(
boost::asio::experimental::wait_for_all(),
[](
std::vector<std::size_t> completion_order,
std::vector<boost::system::error_code> ec,
std::vector<std::size_t> n
)
{
for (std::size_t i = 0; i < completion_order.size(); ++i)
{
std::size_t idx = completion_order[i];
std::cout << "operation " << idx << " finished: ";
std::cout << ec[idx] << ", " << n[idx] << "\n";
}
}
);
ctx.run();
}
#else
int main() {}
#endif