80 lines
1.8 KiB
Plaintext
80 lines
1.8 KiB
Plaintext
[/
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/ Copyright (c) 2003-2019 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:WriteHandler Write handler requirements]
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A write handler must meet the requirements for a [link
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boost_asio.reference.Handler handler]. A value `h` of a write handler class
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should work correctly in the expression `h(ec, s)`, where `ec` is an lvalue of
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type `const error_code` and `s` is an lvalue of type `const size_t`.
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[heading Examples]
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A free function as a write handler:
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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 handler 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 handler:
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socket.async_write(...
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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 handler 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(...,
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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 handler 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(...,
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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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[endsect]
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