111 lines
2.3 KiB
Plaintext
111 lines
2.3 KiB
Plaintext
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[/
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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:WriteToken Write token requirements]
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A write token is a [link boost_asio.overview.model.completion_tokens completion token]
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for completion signature `void(error_code, size_t)`.
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[heading Examples]
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A free function as a write token:
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void write_handler(
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const boost::system::error_code& ec,
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std::size_t bytes_transferred)
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{
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...
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}
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A write token function object:
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struct write_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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std::size_t bytes_transferred)
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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 write token:
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socket.async_write_some(...,
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[](const boost::system::error_code& ec,
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std::size_t bytes_transferred)
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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 write token using
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`std::bind()`:
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void my_class::write_handler(
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const boost::system::error_code& ec,
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std::size_t bytes_transferred)
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{
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...
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}
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...
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socket.async_write_some(...,
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std::bind(&my_class::write_handler,
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this, std::placeholders::_1,
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std::placeholders::_2));
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A non-static class member function adapted to a write token using
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`boost::bind()`:
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void my_class::write_handler(
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const boost::system::error_code& ec,
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std::size_t bytes_transferred)
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{
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...
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}
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...
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socket.async_write_some(...,
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boost::bind(&my_class::write_handler,
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this, boost::asio::placeholders::error,
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boost::asio::placeholders::bytes_transferred));
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Using [link boost_asio.reference.use_future use_future] as a write token:
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std::future<std::size_t> f =
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socket.async_write_some(..., boost::asio::use_future);
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...
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try
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{
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std::size_t n = f.get();
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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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Using [link boost_asio.reference.use_awaitable use_awaitable] as a write 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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std::size_t n =
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co_await socket.async_write_some(
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..., 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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