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Date: Tue, 4 Jan 2005 18:58:33 -0800 (PST)
From: Doug White <dwhite@gumbysoft.com>
To: Pawel Jakub Dawidek <pjd@FreeBSD.org>
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cc: arch@freebsd.org
cc: scottl@freebsd.org
Subject: Re: BigDisk project: du(1) 64bit clean.
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On Tue, 4 Jan 2005, Pawel Jakub Dawidek wrote:

> I want you to look at two patches which makes du(1) 64bit clean.
> This work is part of the BigDisk project:
>
> 	http://www.freebsd.org/projects/bigdisk/
>
> The main problem here is that du(1) uses fts(3) and fts_number field from
> one of its structures to store size.
> This field is defined as 'long' so it doesn't give us what we want
> (on 32bit archs).

No offense intended, but can we avoid introducing LP64 bugs, please?
Particularly when the goal is "ABI compatibility."*

dwlab3,ttyp1,~,24>uname -m
i386
dwlab3,ttyp1,~,25>./test
sizeof(long) [4] + sizeof(void *) [4] == 8 == sizeof(int64_t) [8]

ok .. but:

dwlab4,ttyp1,~,20>uname -m
amd64
dwlab4,ttyp1,~,21>./test
sizeof(long) [8] + sizeof(void *) [8] == 16 != sizeof(int64_t) [8]

oops! The struct just grew by 8 bytes!

(*) On the same platform, obviously.

-- 
Doug White                    |  FreeBSD: The Power to Serve
dwhite@gumbysoft.com          |  www.FreeBSD.org