[/ / 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:SyncReadStream Buffer-oriented synchronous read stream requirements] A type `X` meets the `SyncReadStream` 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 `ec` denotes an object of type `error_code`. [table SyncReadStream requirements [[operation] [type] [semantics, pre/post-conditions]] [ [`a.read_some(mb)`[br] `a.read_some(mb,ec)`] [`size_t`] [ Meets the requirements for a [link boost_asio.reference.read_write_operations read operation].[br] [br] If `buffer_size(mb) > 0`, reads one or more bytes of data from the stream `a` into the buffer sequence `mb`. If successful, sets `ec` such that `!ec` is `true`, and returns the number of bytes read. If an error occurred, sets `ec` such that `!!ec` is `true`, and returns 0. If all data has been read from the stream, and the stream performed an orderly shutdown, sets `ec` to `stream_errc::eof` and returns 0.[br] [br] If `buffer_size(mb) == 0`, the operation shall not block. Sets `ec` such that `!ec` is `true`, and returns 0. ] ] ] [endsect]