The async_read_at function is a composed asynchronous operation that reads a certain amount of data at the specified offset.

Start an asynchronous operation to read a certain amount of data at the specified offset.

template<
    typename AsyncRandomAccessReadDevice,
    typename MutableBufferSequence,
    typename ReadToken = DEFAULT>
DEDUCED async_read_at(
    AsyncRandomAccessReadDevice & d,
    uint64_t offset,
    const MutableBufferSequence & buffers,
    ReadToken && token = DEFAULT);
  » more...

template<
    typename AsyncRandomAccessReadDevice,
    typename MutableBufferSequence,
    typename CompletionCondition,
    typename ReadToken = DEFAULT>
DEDUCED async_read_at(
    AsyncRandomAccessReadDevice & d,
    uint64_t offset,
    const MutableBufferSequence & buffers,
    CompletionCondition completion_condition,
    ReadToken && token = DEFAULT);
  » more...

template<
    typename AsyncRandomAccessReadDevice,
    typename Allocator,
    typename ReadToken = DEFAULT>
DEDUCED async_read_at(
    AsyncRandomAccessReadDevice & d,
    uint64_t offset,
    basic_streambuf< Allocator > & b,
    ReadToken && token = DEFAULT);
  » more...

template<
    typename AsyncRandomAccessReadDevice,
    typename Allocator,
    typename CompletionCondition,
    typename ReadToken = DEFAULT>
DEDUCED async_read_at(
    AsyncRandomAccessReadDevice & d,
    uint64_t offset,
    basic_streambuf< Allocator > & b,
    CompletionCondition completion_condition,
    ReadToken && token = DEFAULT);
  » more...

Requirements

Header: asio/read_at.hpp

Convenience header: asio.hpp