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Date: Wed, 23 Aug 1995 06:11:26 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199508222011.GAA21010@godzilla.zeta.org.au>
To: msmith@atrad.adelaide.edu.au, terry@cs.weber.edu
Subject: Re: Using space in a DOS filesystem
Cc: hackers@freebsd.org
Sender: hackers-owner@freebsd.org
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>> > 1)	Look up the file
>> > 2)	Assert a mandatory file lock
>> 
>> Instructions on this one would be needed 8)

>Open it O_EXCL in the device node exporting code.

In FreeBSD, unlike in Terryx :-), O_EXCL is only implemented for regular
files.  The semantics of O_EXCL are specified by POSIX (only) for
regular files.  They don't give mandatory locking.  Everything that
opens the file would have to use O_EXCL to give advisory locking.

Bruce