posix::descriptor::io_control (2 of 2 overloads)

Perform an IO control command on the descriptor.

template<
    typename IoControlCommand>
void io_control(
    IoControlCommand & command,
    asio::error_code & ec);

This function is used to execute an IO control command on the descriptor.

Parameters

command: The IO control command to be performed on the descriptor.
ec: Set to indicate what error occurred, if any.

Example

Getting the number of bytes ready to read:

asio::posix::stream_descriptor descriptor(io_context);
...
asio::posix::stream_descriptor::bytes_readable command;
asio::error_code ec;
descriptor.io_control(command, ec);
if (ec)
{
  // An error occurred.
}
std::size_t bytes_readable = command.get();