100 lines
1.9 KiB
Plaintext
100 lines
1.9 KiB
Plaintext
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/ Copyright (c) 2003-2023 Christopher M. Kohlhoff (chris at kohlhoff dot com)
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/
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/ Distributed under the Boost Software License, Version 1.0. (See accompanying
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/ file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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/]
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[section:WaitToken Wait token requirements]
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A wait token is a [link boost_asio.overview.model.completion_tokens completion token]
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for completion signature `void(error_code)`.
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[heading Examples]
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A free function as a wait token:
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void wait_handler(
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const boost::system::error_code& ec)
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{
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...
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}
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A wait token function object:
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struct wait_handler
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{
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...
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void operator()(
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const boost::system::error_code& ec)
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{
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...
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}
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...
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};
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A lambda as a wait token:
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socket.async_wait(...,
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[](const boost::system::error_code& ec)
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{
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...
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});
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A non-static class member function adapted to a wait token using
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`std::bind()`:
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void my_class::wait_handler(
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const boost::system::error_code& ec)
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{
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...
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}
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...
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socket.async_wait(...,
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std::bind(&my_class::wait_handler,
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this, std::placeholders::_1));
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A non-static class member function adapted to a wait token using
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`boost::bind()`:
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void my_class::wait_handler(
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const boost::system::error_code& ec)
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{
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...
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}
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...
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socket.async_wait(...,
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boost::bind(&my_class::wait_handler,
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this, boost::asio::placeholders::error));
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Using [link boost_asio.reference.use_future use_future] as a wait token:
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std::future<void> f = socket.async_wait(..., boost::asio::use_future);
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...
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try
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{
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f.get();
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}
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catch (const system_error& e)
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{
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...
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}
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Using [link boost_asio.reference.use_awaitable use_awaitable] as a wait token:
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boost::asio::awaitable<void> my_coroutine()
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{
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try
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{
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...
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co_await socket.async_wait(..., boost::asio::use_awaitable);
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...
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}
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catch (const system_error& e)
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{
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...
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}
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}
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[endsect]
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