From: Francis Cianfrocca <garbagecat10@...>
Date: 2006-05-09T09:45:33+09:00
Subject: Re: Considering Ruby For a Networking Application

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From what you said, this code doesn't do what you think it should do:

# hmm, io/nonblock refuses to work on windows because
# of missing GETFL :(  Just fake it...
if RUBY_PLATFORM =3D~ /mswin32/
  class IO
    def nonblock=3D(nb)
      fcntl(Fcntl::F_SETFL, nb ? Fcntl::O_NONBLOCK : 0)
    end
  end
end

That's because on Windows, this isn't the way to set sockets nonblocking.
Microsoft reinvented a lot of wheels in Windows, and this is one of 'em. Tr=
y
this C code instead (I'll leave it to you to turn it into Ruby):

unsigned long one =3D 1;
ioctlsocket (the_socket_descriptor, FIONBIO, &one);

This will return non-zero in case of error (I've never seen it return an
error).
Best
-francis



On 5/8/06, Bill Kelly <billk@cts.com> wrote:
>
> From: "James Edward Gray II" <james@grayproductions.net>
> >
> > On May 8, 2006, at 12:12 PM, Francis Cianfrocca wrote:
> >
> >> If your performance and scalability requirements are low, then the
> >> easiest thing is
> >> probably to use blocking i/o with a thread per socket. If you use
> >> blocking
> >> i/o, you're better off multiplexing the i/o with a select loop.
> >
> > But then a large write could still block the entire process, since
> > Ruby's threads aren't native.  Right?
>
> Judging from the results of my test program on Linux and
> Windows, it appears nonblocking writes are supported in
> 1.8.4.
>
> ruby 1.8.4 (2005-12-24) [i686-linux]
> ruby 1.8.4 (2005-12-24) [i386-mswin32]
>
> Interestingly, while the Linux version behaved as expected,
> displaying blocking characteristics until I explicitly set
> nonblock=3Dtrue, the windows version appears to sport some
> sort of always-on nonblocking buffered implementation behind
> the scenes now.
>
> On Windows, even if I never set nonblock=3Dtrue, I could syswrite
> 40 megs to the socket and #syswrite would return immediately!
> (Subsequent syswrites would then appear to block until the
> data from the previous huge syswrite was consumed; but just the
> ruby thread performing the syswrite was blocked, never the whole
> process.  So anyway there's some kind of dynamic buffering going
> on behind the scenes in the windows implementation--but in any
> case, it never blocked the whole process.  Excellent.)
>
> In my test program (attached) I'm catching just about every
> exception under the sun, including EAGAIN, which I saw being
> done in lib/openssl/buffering.rb.  However, the only
> exception I actually saw raised was EOFError.  (I never tried
> to force an EPIPE condition on the write.)
>
> Anyway, for what it's worth, it appears ruby 1.8.4 now
> definitely supports nonblocking socket I/O on both Linux
> and Windows!!  Yay!
>
> I'll still be looking at EventMachine though.  :)
>
>
> Regards,
>
> Bill
>
>
>
>

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