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[/
/ Copyright (c) 2003-2020 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:WriteHandler Write handler requirements]
A write handler must meet the requirements for a [link
boost_asio.reference.Handler handler]. A value `h` of a write handler class
should work correctly in the expression `h(ec, s)`, where `ec` is an lvalue of
type `const error_code` and `s` is an lvalue of type `const size_t`.
[heading Examples]
A free function as a write handler:
void write_handler(
const boost::system::error_code& ec,
std::size_t bytes_transferred)
{
...
}
A write handler function object:
struct write_handler
{
...
void operator()(
const boost::system::error_code& ec,
std::size_t bytes_transferred)
{
...
}
...
};
A lambda as a write handler:
socket.async_write(...
[](const boost::system::error_code& ec,
std::size_t bytes_transferred)
{
...
});
A non-static class member function adapted to a write handler using
`std::bind()`:
void my_class::write_handler(
const boost::system::error_code& ec,
std::size_t bytes_transferred)
{
...
}
...
socket.async_write(...,
std::bind(&my_class::write_handler,
this, std::placeholders::_1,
std::placeholders::_2));
A non-static class member function adapted to a write handler using
`boost::bind()`:
void my_class::write_handler(
const boost::system::error_code& ec,
std::size_t bytes_transferred)
{
...
}
...
socket.async_write(...,
boost::bind(&my_class::write_handler,
this, boost::asio::placeholders::error,
boost::asio::placeholders::bytes_transferred));
[endsect]
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