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[/
/ Copyright (c) 2003-2025 Christopher M. Kohlhoff (chris at kohlhoff dot com)
/
/ Distributed under the Boost Software License, Version 1.0. (See accompanying
/ file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
/]
[section:channels Channels]
[note This is an experimental feature.]
The templates
[link boost_asio.reference.experimental__basic_channel experimental::basic_channel]
and [link boost_asio.reference.experimental__basic_concurrent_channel
experimental::basic_concurrent_channel], with aliases `experimental::channel`
and `experimental::concurrent_channel`, may be used to send messages between
different parts of the same application. A ['message] is defined as a
collection of arguments to be passed to a completion handler, and the set of
messages supported by a channel is specified by its template parameters.
Messages may be sent and received using asynchronous or non-blocking
synchronous operations.
For example:
// Create a channel with no buffer space.
channel<void(error_code, size_t)> ch(ctx);
// The call to try_send fails as there is no buffer
// space and no waiting receive operations.
bool ok = ch.try_send(boost::asio::error::eof, 123);
assert(!ok);
// The async_send operation is outstanding until
// a receive operation consumes the message.
ch.async_send(boost::asio::error::eof, 123,
[](error_code ec)
{
// ...
});
// The async_receive consumes the message. Both the
// async_send and async_receive operations complete
// immediately.
ch.async_receive(
[](error_code ec, size_t n)
{
// ...
});
[heading See Also]
[link boost_asio.reference.experimental__basic_channel experimental::basic_channel],
[link boost_asio.reference.experimental__basic_concurrent_channel experimental::basic_concurrent_channel],
[link boost_asio.examples.cpp20_examples.channels Channels examples (C++20)].
[endsect]
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