From owner-freebsd-arch  Mon Jan 13 20:15:21 2003
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Date: Mon, 13 Jan 2003 20:15:14 -0800 (PST)
From: Matthew Dillon <dillon@apollo.backplane.com>
Message-Id: <200301140415.h0E4FEuJ078072@apollo.backplane.com>
To: "Alan L. Cox" <alc@imimic.com>
Cc: Peter Wemm <peter@wemm.org>, arch@FreeBSD.ORG
Subject: Re: Virtual memory question
References: <20030114002831.1C8C12A89E@canning.wemm.org> <3E2381F8.85BB90A0@imimic.com> <200301140339.h0E3dVQa073160@apollo.backplane.com> <3E238DEF.14DFA7E1@imimic.com>
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:I'm happy with the NULL path as an extension to this interface.
:
:>     (2) I don't see how/where one specifies the size of the memory object
:>         in shm_open().  Does this mean we have to implement ftruncate()?
:
:I think the size is implied by the mmap()ing.  A second, larger
:mmap()ing would have to grow the object.  An object should never shrink.
: 
:Regards,
:Alan

    "Ick".  But it would be extremely easy to implement that sort of 
    auto-grow.  I'll read up on the shm_open() spec.  Personally speaking
    I'd like an explicit size to be specified during the open/creation phase.

    It occurs to me that we could use this to implement far better MFS / MD 
    support then we have now.  Hrmmm.

					-Matt
					Matthew Dillon 
					<dillon@backplane.com>


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