[/
 / 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:AsyncReadStream Buffer-oriented asynchronous read stream requirements]

A type `X` meets the `AsyncReadStream` requirements if it satisfies the
requirements listed below.

In the table below, `a` denotes a value of type `X`, `mb` denotes a (possibly
const) value satisfying the [link boost_asio.reference.MutableBufferSequence
`MutableBufferSequence`] requirements, and `t` is a completion token.

[table AsyncReadStream requirements
  [[operation] [type] [semantics, pre/post-conditions]]
  [
    [`a.get_executor()`]
    [A type satisfying the [link boost_asio.reference.Executor1 Executor requirements].]
    [Returns the associated I/O executor.]
  ]
  [
    [`a.async_read_some(mb,t)`]
    [
      The return type is determined according to the requirements for an
      [link boost_asio.reference.asynchronous_operations asynchronous operation].
    ]
    [
      Meets the requirements for a [link boost_asio.reference.read_write_operations
      read operation] and an [link boost_asio.reference.asynchronous_operations
      asynchronous operation] with completion signature `void(error_code ec,
      size_t n)`.[br]
      [br]
      If `buffer_size(mb) > 0`, initiates an asynchronous operation to read one
      or more bytes of data from the stream `a` into the buffer sequence `mb`.
      If successful, `ec` is set such that `!ec` is `true`, and `n` is the
      number of bytes read. If an error occurred, `ec` is set such that `!!ec`
      is `true`, and `n` is 0. If all data has been read from the stream, and
      the stream performed an orderly shutdown, `ec` is
      `stream_errc::eof` and `n` is 0.[br]
      [br]
      If `buffer_size(mb) == 0`, the operation completes immediately. `ec` is
      set such that `!ec` is `true`, and `n` is 0.
    ]
  ]
]

[endsect]