Начните асинхронную операцию, чтобы прочитать определенное количество данных в указанном смещении.

template<
    typename AsyncRandomAccessReadDevice,
    typename MutableBufferSequence,
    typename ReadHandler>
void-or-deduced async_read_at(
    AsyncRandomAccessReadDevice & d,
    uint64_t offset,
    const MutableBufferSequence & buffers,
    ReadHandler handler);
  » more...
template<
    typename AsyncRandomAccessReadDevice,
    typename MutableBufferSequence,
    typename CompletionCondition,
    typename ReadHandler>
void-or-deduced async_read_at(
    AsyncRandomAccessReadDevice & d,
    uint64_t offset,
    const MutableBufferSequence & buffers,
    CompletionCondition completion_condition,
    ReadHandler handler);
  » more...
template<
    typename AsyncRandomAccessReadDevice,
    typename Allocator,
    typename ReadHandler>
void-or-deduced async_read_at(
    AsyncRandomAccessReadDevice & d,
    uint64_t offset,
    basic_streambuf< Allocator > & b,
    ReadHandler handler);
  » more...
template<
    typename AsyncRandomAccessReadDevice,
    typename Allocator,
    typename CompletionCondition,
    typename ReadHandler>
void-or-deduced async_read_at(
    AsyncRandomAccessReadDevice & d,
    uint64_t offset,
    basic_streambuf< Allocator > & b,
    CompletionCondition completion_condition,
    ReadHandler handler);
  » more...

Requirements

Здитель: >boost/asio/read_at.hpp

Заголовок: boost/asio.hpp