Gets the non-blocking mode of the native descriptor implementation.
bool native_non_blocking() const;
This function is used to retrieve the non-blocking mode of the underlying native descriptor. This mode has no effect on the behaviour of the descriptor object's synchronous operations.
true if the underlying descriptor
is in non-blocking mode and direct system calls may fail with
asio::error::would_block (or the equivalent system
The current non-blocking mode is cached by the descriptor object. Consequently, the return value may be incorrect if the non-blocking mode was set directly on the native descriptor.