58 lines
2.3 KiB
Plaintext
58 lines
2.3 KiB
Plaintext
[/
|
|
/ Copyright (c) 2003-2019 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:AsyncRandomAccessWriteDevice Buffer-oriented asynchronous
|
|
random-access write device requirements]
|
|
|
|
In the table below, `a` denotes an asynchronous write stream object, `o`
|
|
denotes an offset of type `boost::uint64_t`, `cb` denotes an object satisfying
|
|
[link boost_asio.reference.ConstBufferSequence constant buffer sequence]
|
|
requirements, and `h` denotes an object satisfying [link
|
|
boost_asio.reference.WriteHandler write handler] requirements.
|
|
|
|
[table Buffer-oriented asynchronous random-access write device 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_write_some_at(o, cb, h);`]
|
|
[`void`]
|
|
[
|
|
Initiates an asynchronous operation to write one or more bytes of data to
|
|
the device `a` at offset `o`. The operation is performed via the
|
|
`io_service` object `a.get_io_service()` and behaves according to [link
|
|
boost_asio.reference.asynchronous_operations asynchronous operation]
|
|
requirements.\n
|
|
\n
|
|
The constant buffer sequence `cb` specifies memory where the data to be
|
|
written is located. The `async_write_some_at` operation shall always
|
|
write a buffer in the sequence completely before proceeding to the
|
|
next.\n
|
|
\n
|
|
The implementation shall maintain one or more copies of `cb` until such
|
|
time as the write operation no longer requires access to the memory
|
|
specified by the buffers in the sequence. The program must ensure the
|
|
memory is valid until:\n
|
|
\n
|
|
[mdash] the last copy of `cb` is destroyed, or\n
|
|
\n
|
|
[mdash] the handler for the asynchronous write operation is invoked,\n
|
|
\n
|
|
whichever comes first.\n
|
|
\n
|
|
If the total size of all buffers in the sequence `cb` is `0`, the
|
|
asynchronous write operation shall complete immediately and pass `0` as
|
|
the argument to the handler that specifies the number of bytes written.
|
|
]
|
|
]
|
|
]
|
|
|
|
[endsect]
|