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From: mmdf@udel.UUCP
Newsgroups: comp.os.minix
Subject: Size specifications on MINIX special files
Message-ID: <570@louie.udel.EDU>
Date: Thu, 8-Oct-87 13:52:42 EDT
Article-I.D.: louie.570
Posted: Thu Oct  8 13:52:42 1987
Date-Received: Sun, 11-Oct-87 03:29:57 EDT
Sender: mmdf@udel.EDU
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In <569@louie.udel.EDU> Marty writes:

>I'm not sure where f_size would come from for a block special device,
>but if its
>not 0, read won't allow read's beyond the limit of f_size.  Why bother
>checking f_size at all (which comes out of the inode's i_size field).

Someone correct me if I'm wrong, but my understanding was that MINIX,
unlike UNIX, supports the use of a size in the inodes of special
devices. I think that this is a deliberate feature designed to prevent
reading past the end of a device. For example, the inadvertent mounting
of a 360K file system on a 1.2M floppy disk drive. The "fix" suggested
in this mail would, I believe, defeat this protection. I wonder what the
result would be? I guess I'll never know.

Gary
Ultra!Gary@Ames.ARPA