527 lines
20 KiB
C++
527 lines
20 KiB
C++
//
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// read.hpp
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// ~~~~~~~~
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//
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// Copyright (c) 2003-2008 Christopher M. Kohlhoff (chris at kohlhoff dot com)
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//
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// Distributed under the Boost Software License, Version 1.0. (See accompanying
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// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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//
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#ifndef ASIO_READ_HPP
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#define ASIO_READ_HPP
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#if defined(_MSC_VER) && (_MSC_VER >= 1200)
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# pragma once
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#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
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#include "asio/detail/push_options.hpp"
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#include "asio/detail/push_options.hpp"
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#include <cstddef>
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#include <boost/config.hpp>
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#include "asio/detail/pop_options.hpp"
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#include "asio/basic_streambuf.hpp"
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#include "asio/error.hpp"
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namespace asio {
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/**
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* @defgroup read asio::read
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*
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* @brief Attempt to read a certain amount of data from a stream before
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* returning.
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*/
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/*@{*/
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/// Attempt to read a certain amount of data from a stream before returning.
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/**
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* This function is used to read a certain number of bytes of data from a
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* stream. The call will block until one of the following conditions is true:
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*
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* @li The supplied buffers are full. That is, the bytes transferred is equal to
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* the sum of the buffer sizes.
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*
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* @li An error occurred.
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*
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* This operation is implemented in terms of zero or more calls to the stream's
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* read_some function.
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*
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* @param s The stream from which the data is to be read. The type must support
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* the SyncReadStream concept.
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*
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* @param buffers One or more buffers into which the data will be read. The sum
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* of the buffer sizes indicates the maximum number of bytes to read from the
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* stream.
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*
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* @returns The number of bytes transferred.
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*
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* @throws asio::system_error Thrown on failure.
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*
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* @par Example
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* To read into a single data buffer use the @ref buffer function as follows:
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* @code asio::read(s, asio::buffer(data, size)); @endcode
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* See the @ref buffer documentation for information on reading into multiple
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* buffers in one go, and how to use it with arrays, boost::array or
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* std::vector.
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*
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* @note This overload is equivalent to calling:
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* @code asio::read(
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* s, buffers,
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* asio::transfer_all()); @endcode
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*/
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template <typename SyncReadStream, typename MutableBufferSequence>
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std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers);
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/// Attempt to read a certain amount of data from a stream before returning.
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/**
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* This function is used to read a certain number of bytes of data from a
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* stream. The call will block until one of the following conditions is true:
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*
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* @li The supplied buffers are full. That is, the bytes transferred is equal to
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* the sum of the buffer sizes.
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*
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* @li The completion_condition function object returns true.
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*
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* This operation is implemented in terms of zero or more calls to the stream's
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* read_some function.
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*
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* @param s The stream from which the data is to be read. The type must support
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* the SyncReadStream concept.
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*
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* @param buffers One or more buffers into which the data will be read. The sum
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* of the buffer sizes indicates the maximum number of bytes to read from the
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* stream.
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*
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* @param completion_condition The function object to be called to determine
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* whether the read operation is complete. The signature of the function object
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* must be:
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* @code std::size_t completion_condition(
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* // Result of latest read_some operation.
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* const asio::error_code& error,
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*
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* // Number of bytes transferred so far.
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* std::size_t bytes_transferred
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* ); @endcode
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* A return value of 0 indicates that the read operation is complete. A non-zero
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* return value indicates the maximum number of bytes to be read on the next
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* call to the stream's read_some function.
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*
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* @returns The number of bytes transferred.
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*
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* @throws asio::system_error Thrown on failure.
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*
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* @par Example
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* To read into a single data buffer use the @ref buffer function as follows:
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* @code asio::read(s, asio::buffer(data, size),
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* asio::transfer_at_least(32)); @endcode
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* See the @ref buffer documentation for information on reading into multiple
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* buffers in one go, and how to use it with arrays, boost::array or
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* std::vector.
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*/
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template <typename SyncReadStream, typename MutableBufferSequence,
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typename CompletionCondition>
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std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers,
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CompletionCondition completion_condition);
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/// Attempt to read a certain amount of data from a stream before returning.
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/**
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* This function is used to read a certain number of bytes of data from a
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* stream. The call will block until one of the following conditions is true:
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*
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* @li The supplied buffers are full. That is, the bytes transferred is equal to
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* the sum of the buffer sizes.
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*
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* @li The completion_condition function object returns true.
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*
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* This operation is implemented in terms of zero or more calls to the stream's
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* read_some function.
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*
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* @param s The stream from which the data is to be read. The type must support
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* the SyncReadStream concept.
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*
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* @param buffers One or more buffers into which the data will be read. The sum
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* of the buffer sizes indicates the maximum number of bytes to read from the
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* stream.
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*
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* @param completion_condition The function object to be called to determine
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* whether the read operation is complete. The signature of the function object
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* must be:
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* @code std::size_t completion_condition(
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* // Result of latest read_some operation.
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* const asio::error_code& error,
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*
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* // Number of bytes transferred so far.
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* std::size_t bytes_transferred
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* ); @endcode
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* A return value of 0 indicates that the read operation is complete. A non-zero
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* return value indicates the maximum number of bytes to be read on the next
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* call to the stream's read_some function.
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*
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* @param ec Set to indicate what error occurred, if any.
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*
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* @returns The number of bytes read. If an error occurs, returns the total
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* number of bytes successfully transferred prior to the error.
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*/
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template <typename SyncReadStream, typename MutableBufferSequence,
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typename CompletionCondition>
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std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers,
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CompletionCondition completion_condition, asio::error_code& ec);
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/// Attempt to read a certain amount of data from a stream before returning.
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/**
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* This function is used to read a certain number of bytes of data from a
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* stream. The call will block until one of the following conditions is true:
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*
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* @li An error occurred.
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*
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* This operation is implemented in terms of zero or more calls to the stream's
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* read_some function.
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*
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* @param s The stream from which the data is to be read. The type must support
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* the SyncReadStream concept.
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*
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* @param b The basic_streambuf object into which the data will be read.
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*
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* @returns The number of bytes transferred.
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*
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* @throws asio::system_error Thrown on failure.
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*
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* @note This overload is equivalent to calling:
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* @code asio::read(
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* s, b,
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* asio::transfer_all()); @endcode
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*/
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template <typename SyncReadStream, typename Allocator>
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std::size_t read(SyncReadStream& s, basic_streambuf<Allocator>& b);
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/// Attempt to read a certain amount of data from a stream before returning.
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/**
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* This function is used to read a certain number of bytes of data from a
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* stream. The call will block until one of the following conditions is true:
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*
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* @li The completion_condition function object returns true.
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*
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* This operation is implemented in terms of zero or more calls to the stream's
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* read_some function.
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*
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* @param s The stream from which the data is to be read. The type must support
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* the SyncReadStream concept.
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*
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* @param b The basic_streambuf object into which the data will be read.
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*
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* @param completion_condition The function object to be called to determine
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* whether the read operation is complete. The signature of the function object
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* must be:
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* @code std::size_t completion_condition(
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* // Result of latest read_some operation.
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* const asio::error_code& error,
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*
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* // Number of bytes transferred so far.
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* std::size_t bytes_transferred
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* ); @endcode
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* A return value of 0 indicates that the read operation is complete. A non-zero
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* return value indicates the maximum number of bytes to be read on the next
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* call to the stream's read_some function.
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*
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* @returns The number of bytes transferred.
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*
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* @throws asio::system_error Thrown on failure.
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*/
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template <typename SyncReadStream, typename Allocator,
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typename CompletionCondition>
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std::size_t read(SyncReadStream& s, basic_streambuf<Allocator>& b,
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CompletionCondition completion_condition);
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/// Attempt to read a certain amount of data from a stream before returning.
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/**
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* This function is used to read a certain number of bytes of data from a
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* stream. The call will block until one of the following conditions is true:
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*
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* @li The completion_condition function object returns true.
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*
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* This operation is implemented in terms of zero or more calls to the stream's
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* read_some function.
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*
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* @param s The stream from which the data is to be read. The type must support
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* the SyncReadStream concept.
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*
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* @param b The basic_streambuf object into which the data will be read.
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*
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* @param completion_condition The function object to be called to determine
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* whether the read operation is complete. The signature of the function object
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* must be:
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* @code std::size_t completion_condition(
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* // Result of latest read_some operation.
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* const asio::error_code& error,
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*
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* // Number of bytes transferred so far.
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* std::size_t bytes_transferred
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* ); @endcode
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* A return value of 0 indicates that the read operation is complete. A non-zero
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* return value indicates the maximum number of bytes to be read on the next
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* call to the stream's read_some function.
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*
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* @param ec Set to indicate what error occurred, if any.
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*
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* @returns The number of bytes read. If an error occurs, returns the total
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* number of bytes successfully transferred prior to the error.
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*/
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template <typename SyncReadStream, typename Allocator,
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typename CompletionCondition>
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std::size_t read(SyncReadStream& s, basic_streambuf<Allocator>& b,
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CompletionCondition completion_condition, asio::error_code& ec);
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/*@}*/
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/**
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* @defgroup async_read asio::async_read
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*
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* @brief Start an asynchronous operation to read a certain amount of data from
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* a stream.
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*/
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/*@{*/
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/// Start an asynchronous operation to read a certain amount of data from a
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/// stream.
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/**
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* This function is used to asynchronously read a certain number of bytes of
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* data from a stream. The function call always returns immediately. The
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* asynchronous operation will continue until one of the following conditions is
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* true:
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*
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* @li The supplied buffers are full. That is, the bytes transferred is equal to
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* the sum of the buffer sizes.
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*
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* @li An error occurred.
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*
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* This operation is implemented in terms of zero or more calls to the stream's
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* async_read_some function.
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*
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* @param s The stream from which the data is to be read. The type must support
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* the AsyncReadStream concept.
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*
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* @param buffers One or more buffers into which the data will be read. The sum
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* of the buffer sizes indicates the maximum number of bytes to read from the
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* stream. Although the buffers object may be copied as necessary, ownership of
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* the underlying memory blocks is retained by the caller, which must guarantee
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* that they remain valid until the handler is called.
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*
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* @param handler The handler to be called when the read operation completes.
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* Copies will be made of the handler as required. The function signature of the
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* handler must be:
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* @code void handler(
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* const asio::error_code& error, // Result of operation.
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*
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* std::size_t bytes_transferred // Number of bytes copied into the
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* // buffers. If an error occurred,
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* // this will be the number of
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* // bytes successfully transferred
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* // prior to the error.
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* ); @endcode
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* Regardless of whether the asynchronous operation completes immediately or
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* not, the handler will not be invoked from within this function. Invocation of
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* the handler will be performed in a manner equivalent to using
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* asio::io_service::post().
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*
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* @par Example
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* To read into a single data buffer use the @ref buffer function as follows:
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* @code
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* asio::async_read(s, asio::buffer(data, size), handler);
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* @endcode
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* See the @ref buffer documentation for information on reading into multiple
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* buffers in one go, and how to use it with arrays, boost::array or
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* std::vector.
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*
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* @note This overload is equivalent to calling:
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* @code asio::async_read(
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* s, buffers,
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* asio::transfer_all(),
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* handler); @endcode
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*/
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template <typename AsyncReadStream, typename MutableBufferSequence,
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typename ReadHandler>
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void async_read(AsyncReadStream& s, const MutableBufferSequence& buffers,
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ReadHandler handler);
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/// Start an asynchronous operation to read a certain amount of data from a
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/// stream.
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/**
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* This function is used to asynchronously read a certain number of bytes of
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* data from a stream. The function call always returns immediately. The
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* asynchronous operation will continue until one of the following conditions is
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* true:
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*
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* @li The supplied buffers are full. That is, the bytes transferred is equal to
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* the sum of the buffer sizes.
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*
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* @li The completion_condition function object returns true.
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*
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* @param s The stream from which the data is to be read. The type must support
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* the AsyncReadStream concept.
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*
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* @param buffers One or more buffers into which the data will be read. The sum
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* of the buffer sizes indicates the maximum number of bytes to read from the
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* stream. Although the buffers object may be copied as necessary, ownership of
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* the underlying memory blocks is retained by the caller, which must guarantee
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* that they remain valid until the handler is called.
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*
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* @param completion_condition The function object to be called to determine
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* whether the read operation is complete. The signature of the function object
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* must be:
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* @code std::size_t completion_condition(
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* // Result of latest async_read_some operation.
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* const asio::error_code& error,
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*
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* // Number of bytes transferred so far.
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* std::size_t bytes_transferred
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* ); @endcode
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* A return value of 0 indicates that the read operation is complete. A non-zero
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* return value indicates the maximum number of bytes to be read on the next
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* call to the stream's async_read_some function.
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*
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* @param handler The handler to be called when the read operation completes.
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* Copies will be made of the handler as required. The function signature of the
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* handler must be:
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* @code void handler(
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* const asio::error_code& error, // Result of operation.
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*
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* std::size_t bytes_transferred // Number of bytes copied into the
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* // buffers. If an error occurred,
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* // this will be the number of
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* // bytes successfully transferred
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* // prior to the error.
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* ); @endcode
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* Regardless of whether the asynchronous operation completes immediately or
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* not, the handler will not be invoked from within this function. Invocation of
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* the handler will be performed in a manner equivalent to using
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* asio::io_service::post().
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*
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* @par Example
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* To read into a single data buffer use the @ref buffer function as follows:
|
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* @code asio::async_read(s,
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* asio::buffer(data, size),
|
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* asio::transfer_at_least(32),
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* handler); @endcode
|
|
* See the @ref buffer documentation for information on reading into multiple
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* buffers in one go, and how to use it with arrays, boost::array or
|
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* std::vector.
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*/
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template <typename AsyncReadStream, typename MutableBufferSequence,
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typename CompletionCondition, typename ReadHandler>
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void async_read(AsyncReadStream& s, const MutableBufferSequence& buffers,
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CompletionCondition completion_condition, ReadHandler handler);
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|
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/// Start an asynchronous operation to read a certain amount of data from a
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/// stream.
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/**
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|
* This function is used to asynchronously read a certain number of bytes of
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* data from a stream. The function call always returns immediately. The
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* asynchronous operation will continue until one of the following conditions is
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* true:
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*
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* @li An error occurred.
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*
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* This operation is implemented in terms of zero or more calls to the stream's
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* async_read_some function.
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|
*
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* @param s The stream from which the data is to be read. The type must support
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|
* the AsyncReadStream concept.
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|
*
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* @param b A basic_streambuf object into which the data will be read. Ownership
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|
* of the streambuf is retained by the caller, which must guarantee that it
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* remains valid until the handler is called.
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*
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* @param handler The handler to be called when the read operation completes.
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|
* Copies will be made of the handler as required. The function signature of the
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* handler must be:
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* @code void handler(
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* const asio::error_code& error, // Result of operation.
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*
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* std::size_t bytes_transferred // Number of bytes copied into the
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* // buffers. If an error occurred,
|
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* // this will be the number of
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* // bytes successfully transferred
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* // prior to the error.
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* ); @endcode
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* Regardless of whether the asynchronous operation completes immediately or
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|
* not, the handler will not be invoked from within this function. Invocation of
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* the handler will be performed in a manner equivalent to using
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* asio::io_service::post().
|
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*
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* @note This overload is equivalent to calling:
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* @code asio::async_read(
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* s, b,
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* asio::transfer_all(),
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* handler); @endcode
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*/
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template <typename AsyncReadStream, typename Allocator, typename ReadHandler>
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void async_read(AsyncReadStream& s, basic_streambuf<Allocator>& b,
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ReadHandler handler);
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|
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/// Start an asynchronous operation to read a certain amount of data from a
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/// stream.
|
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/**
|
|
* This function is used to asynchronously read a certain number of bytes of
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* data from a stream. The function call always returns immediately. The
|
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* asynchronous operation will continue until one of the following conditions is
|
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* true:
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*
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* @li The completion_condition function object returns true.
|
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*
|
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* This operation is implemented in terms of zero or more calls to the stream's
|
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* async_read_some function.
|
|
*
|
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* @param s The stream from which the data is to be read. The type must support
|
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* the AsyncReadStream concept.
|
|
*
|
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* @param b A basic_streambuf object into which the data will be read. Ownership
|
|
* of the streambuf is retained by the caller, which must guarantee that it
|
|
* remains valid until the handler is called.
|
|
*
|
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* @param completion_condition The function object to be called to determine
|
|
* whether the read operation is complete. The signature of the function object
|
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* must be:
|
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* @code std::size_t completion_condition(
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* // Result of latest async_read_some operation.
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* const asio::error_code& error,
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*
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* // Number of bytes transferred so far.
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* std::size_t bytes_transferred
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* ); @endcode
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* A return value of 0 indicates that the read operation is complete. A non-zero
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* return value indicates the maximum number of bytes to be read on the next
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* call to the stream's async_read_some function.
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|
*
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* @param handler The handler to be called when the read operation completes.
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|
* Copies will be made of the handler as required. The function signature of the
|
|
* handler must be:
|
|
* @code void handler(
|
|
* const asio::error_code& error, // Result of operation.
|
|
*
|
|
* std::size_t bytes_transferred // Number of bytes copied into the
|
|
* // buffers. If an error occurred,
|
|
* // this will be the number of
|
|
* // bytes successfully transferred
|
|
* // prior to the error.
|
|
* ); @endcode
|
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* Regardless of whether the asynchronous operation completes immediately or
|
|
* not, the handler will not be invoked from within this function. Invocation of
|
|
* the handler will be performed in a manner equivalent to using
|
|
* asio::io_service::post().
|
|
*/
|
|
template <typename AsyncReadStream, typename Allocator,
|
|
typename CompletionCondition, typename ReadHandler>
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void async_read(AsyncReadStream& s, basic_streambuf<Allocator>& b,
|
|
CompletionCondition completion_condition, ReadHandler handler);
|
|
|
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/*@}*/
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|
|
|
} // namespace asio
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|
|
|
#include "asio/impl/read.ipp"
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|
|
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#include "asio/detail/pop_options.hpp"
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|
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#endif // ASIO_READ_HPP
|