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Date: Wed, 15 Aug 2012 10:54:15 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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CC: Stanislav Kinsbursky <skinsbursky@parallels.com>, tglx@linutronix.de,
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Subject: Re: [RFC PATCH 0/5] net: socket bind to file descriptor introduced
References: <20120815161141.7598.16682.stgit@localhost.localdomain> <87wr102j2y.fsf@blp.benpfaff.org>
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On 08/15/2012 09:52 AM, Ben Pfaff wrote:
> Stanislav Kinsbursky <skinsbursky@parallels.com> writes:
> 
>> This system call is especially required for UNIX sockets, which has name
>> lenght limitation.
> 
> The worst of the name length limitations can be worked around by
> opening the directory where the socket is to go as a file
> descriptor, then using /proc/self/fd/<fd>/<basename> as the name
> of the socket.  This technique also works with "connect" and in
> other contexts where a struct sockaddr is needed.  At first
> glance, it looks like your patches only help with "bind".
> 

The really hard part is what to do with things that are supposed to
return a struct sockaddr.  I also have some reservations about using a
new system call to deal with what at least theoretically is only part of
one socket domain.

	-hpa