The contract specifies that the file descriptor should already be in
non-blocking mode before passing it to libuv.
However, node users don't really have an opportunity to do so, never
mind the fact that the call to uv_pipe_open() or uv_tcp_open() is an
implementation detail that most users won't be aware of.
Let's be nice and set the non-blocking flag explicitly. It's a cheap
operation anyway.
Fixes: https://github.com/libuv/libuv/issues/124
PR: https://github.com/libuv/libuv/pull/134
Reviewed-by: Saúl Ibarra Corretgé <saghul@gmail.com>
