From owner-freebsd-hackers  Wed May 23  4:38:26 2001
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Date: Wed, 23 May 2001 12:38:21 +0100
From: David Malone <dwmalone@maths.tcd.ie>
To: "Koster, K.J." <K.J.Koster@kpn.com>
Cc: 'Alfred Perlstein' <bright@rush.net>,
	'FreeBSD Hackers mailing list' <freebsd-hackers@freebsd.org>
Subject: Re: Linux getcwd problems
Message-ID: <20010523123821.A52523@walton.maths.tcd.ie>
References: <59063B5B4D98D311BC0D0001FA7E452205FD9C04@l04.research.kpn.com>
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In-Reply-To: <59063B5B4D98D311BC0D0001FA7E452205FD9C04@l04.research.kpn.com>; from K.J.Koster@kpn.com on Wed, May 23, 2001 at 01:02:01PM +0100
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On Wed, May 23, 2001 at 01:02:01PM +0100, Koster, K.J. wrote:

The problem seems to be that FreeBSD's getcwd library call will
impliment the getcwd userland if the syscall fails or is unimplimented.

There are times when the syscall fails in normal operation and you
don't see this with the BSD stuff 'cos it is covered up by the
userland implimentation. You can check this by kdumping a FreeBSD
version of your cwd program and searching for the return value of
the __getcwd syscall.

The Linux emulation stuff just calls the FreeBSD syscall, but I
guess the Linux libraries don't expect getcwd to fail, so they
can't do the userland magic.

I haven't had a chance to look at how hard it would be to fix the
FreeBSD getcwd call to always work, or to fake the Linux stuff so
that it somehow did the equivelent of the userland thing.

	David.

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