public inbox for cygwin@cygwin.com
 help / color / mirror / Atom feed
From: Michael Enright <mike@kmcardiff.com>
To: cygwin@cygwin.com
Subject: Re: Hangs on connect to UNIX socket being listened on in the same process (was: Cygwin hanging in pselect)
Date: Fri, 13 Jan 2017 00:54:00 -0000	[thread overview]
Message-ID: <CAOC2fq9Q24wyBqCqx15oejCiOK88P41vgbZ5Rm0ZUZcxNzwVsg@mail.gmail.com> (raw)
In-Reply-To: <20170112221323.GE23119@calimero.vinschen.de>

On Thu, Jan 12, 2017 at 2:13 PM, Corinna Vinschen
<corinna-cygwin@cygwin.com> wrote:
> Step 3:
>
>   If we did it really intelligent, maybe we finally also have a method
>   to implement descriptor passing.  Finally.  After all these years.
>
> And maybe, we should not actually use the socket itself to exchange
> the information but rather create some kind of side-channle for that.
>
> Especially in terms of step 3, I'm mulling over this for years now
> and always something else got in the way and had to be done first.
>
>

I made a program that needed to pass windows HANDLEs between processes
and so that receiving process could access the shared memory
represented by the HANDLEs. I was emulating facilities many programs
implement using send_msg, but I was using Windows (named?) pipes. It
felt a lot like what you need for send_msg, and it required newer
Windows APIs. So by doing the crazy thing of completely rewriting your
AF_UNIX sockets you could "easily" add descriptor passing.

--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple

  reply	other threads:[~2017-01-13  0:54 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-01-09 13:29 Erik Bray
2017-01-09 14:13 ` Corinna Vinschen
2017-01-09 15:46   ` Erik Bray
2017-01-09 17:16     ` Corinna Vinschen
2017-01-12 10:59       ` Erik Bray
2017-01-12 22:13         ` Corinna Vinschen
2017-01-13  0:54           ` Michael Enright [this message]
2017-01-13  8:42             ` Corinna Vinschen

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=CAOC2fq9Q24wyBqCqx15oejCiOK88P41vgbZ5Rm0ZUZcxNzwVsg@mail.gmail.com \
    --to=mike@kmcardiff.com \
    --cc=cygwin@cygwin.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).