Note
	This feature requires I/O completion ports on Windows, and io_uring on Linux (define BOOST_ASIO_HAS_IO_URING to enable).

Boost.Asio provides support for manipulating stream-oriented and random-access files. For example, to write to a newly created stream-oriented file:

boost::asio::stream_file file(
    my_io_context, "/path/to/file",
    boost::asio::stream_file::write_only
      | boost::asio::stream_file::create
      | boost::asio::stream_file::truncate);

file.async_write_some(my_buffer,
    [](error_code e, size_t n)
    {
      // ...
    });

or to read from a random-access file:

boost::asio::random_access_file file(
    my_io_context, "/path/to/file",
    boost::asio::random_access_file::read_only);

file.async_read_some_at(1234, my_buffer,
    [](error_code e, size_t n)
    {
      // ...
    });

See Also

basic_file, basic_random_access_file, basic_stream_file, file_base, random_access_file, stream_file.