The mutable_registered_buffer and const_registered_buffer classes are
buffer sequence types that represented registered buffers. These buffers
are obtained by first performing a buffer registration:
auto my_registration =
asio::register_buffers(
my_execution_context,
my_buffer_sequence);
The registration object must be maintained for as long as the buffer
registration is required. The supplied buffer sequence represents the
memory location or locations that will be registered, and the caller
must ensure they remain valid for as long as they are registered. The
registration is automatically removed when the registration object is
destroyed. There can be at most one active registration per execution
context.
The registration object is a container of registered buffers. Buffers
may be obtained from it by iterating over the container, or via direct
index access:
asio::mutable_registered_buffer my_buffer
= my_registration[i];
The registered buffers may then be passed directly to operations:
asio::async_read(my_socket, my_buffer,
[](error_code ec, size_t n)
{
// ...
});
Buffer registration supports the io_uring backend when used with read
and write operations on descriptors, files, pipes, and sockets.
