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Message-ID: <01b701c22bf1$d08e88f0$1800a8c0@LAPTOP>
From: "Robert Collins" <robert DOT collins AT syncretize DOT net>
To: <cygwin-developers AT cygwin DOT com>
References: <Pine DOT LNX DOT 4 DOT 33 DOT 0207131534200 DOT 3194-100000 AT this> <20020715103127 DOT A6932 AT cygbert DOT vinschen DOT de> <006b01c22be7$15deadf0$1800a8c0 AT LAPTOP> <20020715131019 DOT C17700 AT cygbert DOT vinschen DOT de>
Subject: Re: How about this for passing file descriptors?
Date: Mon, 15 Jul 2002 21:21:50 +1000
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----- Original Message -----
From: "Corinna Vinschen" <vinschen AT redhat DOT com>
To: <cygwin-developers AT cygwin DOT com>
Sent: Monday, July 15, 2002 9:10 PM

> Perhaps that's not even needed.  We already have a couple of methods
> which are involved when duplicating handles between processes, namely
> dup(), fixup_before_fork(), fixup_after_fork(), fixup_after_exec().

Hmm, the difference being that these methods are all synchronous. generic
passing of file descriptors is not synchronous.

> Basically they are only restricted in their functionality since they
> only get the *parent* process handle.  If we generalize this stuff
> to get a *source* and a *destination* process handle instead, the
> whole stuff would be available for situations besides fork/exec...

Remember that we don't know the destination process handle for this
scenario, all we know is that we need to prepare the fd for *some* process
to recieve.

Rob