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From: Houder <houder@xs4all.nl>
To: cygwin@cygwin.com
Subject: Re: /dev/fd/N not synonymous with file descriptor N; it is on Linux
Date: Mon, 17 Dec 2018 04:30:00 -0000	[thread overview]
Message-ID: <12270f528754c1ce974e6ad8d22c4249@xs4all.nl> (raw)
In-Reply-To: <20181216215549.GO28727@calimero.vinschen.de>

On 2018-12-16 22:55, Corinna Vinschen wrote:
[snip]

> I'm mulling over adding some hack to open().  It could try to recognize
> the special case of opening a processes' own descriptor symlink within
> /proc and then warp the open() call into dup().  No idea how tricky
> or even feasible that is, though...

That is why I wrote the following in my STC:

         // Q: does Cygwin attempt to read the /tmp directory? (an 
attempt that
         //    will fail, because the file has been unlinked)
         // it appears that reading a symlnk in /dev/fd can best be 
diverted to
         // the open file descriptor of the process ...

What I meant was, that I see no reason to modify the symlink in this
special case, but in stead of that to access the file using fd N, where
N is equal to the one in /dev/fd/N.

File descriptor N has been left open by bash and should not have been
closed as result of the exec ...

And indeed, I have _no_ clue if the above is feasible (and tricky?) in
Cygwin; otherwise I would have posted a solution.

Regards,
Henri

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  reply	other threads:[~2018-12-17  4:30 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-12-16 16:31 Houder
2018-12-16 20:28 ` Corinna Vinschen
2018-12-16 20:31   ` Corinna Vinschen
2018-12-16 21:36   ` Wayne Davison
2018-12-16 21:55     ` Corinna Vinschen
2018-12-17  4:30       ` Houder [this message]
2018-12-17  9:25         ` Corinna Vinschen
2018-12-17 11:26           ` Corinna Vinschen
2019-01-02 13:56             ` Houder
2018-12-17  3:41   ` Houder
2019-01-06 20:19 ` Corinna Vinschen
2019-01-22  8:50   ` Houder
2019-01-22  8:57     ` Houder
2019-01-22  9:06       ` Corinna Vinschen
2019-01-22  9:25         ` Houder
2019-01-22  9:42           ` Corinna Vinschen
2019-01-22 10:20             ` Houder
2019-01-22 10:39               ` Corinna Vinschen
2019-01-27 18:39                 ` Houder
2019-01-27 21:57                   ` Corinna Vinschen
2019-01-27 22:12                     ` Corinna Vinschen
2019-01-28 14:15                     ` Houder
2019-01-28 16:51                       ` Corinna Vinschen
2019-01-22  9:02     ` Corinna Vinschen
2019-01-22  9:07       ` Corinna Vinschen

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