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	Tue, 11 Mar 2025 18:11:54 +0000
Date: Tue, 11 Mar 2025 18:11:54 +0000
From: Al Viro <viro@zeniv.linux.org.uk>
To: Theodore Ts'o <tytso@mit.edu>
Cc: David Laight <david.laight.linux@gmail.com>,
	"Artem S. Tashkinov" <aros@gmx.com>, linux-ext4@vger.kernel.org,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: A syscall for changing birth time
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Tue, Mar 11, 2025 at 01:07:25PM -0400, Theodore Ts'o wrote:

> I actually pulled down the V7 sources and there was a comment in
> /usr/sys/h/ino.h which has a comment around the on-disk inode stating
> "creation time" (see below).  These comments are also there up to
> 3BSD, and changed to "inode change time" in the BSD 4.2 sources,
> probably coincident with the BSD Fast File System implementation.

Ken Thompson is at google these days - might be interesting to ask if
there was a point between v6 and v7 where it was used as 'creation
time'.

https://www.tuhs.org/Archive/Documentation/Papers/BSTJ/bstj57-6-1905.pdf
looks like a reference to 'creation time' in Apr 78, and man/man5/filsys.5
is Jan 79 (already matching actual behaviour of released v7).

I wonder if anything of Interdata 8/32 port survives...