- From: Steve Carter <SRCarter@novell.com>
- Date: Fri, 21 Feb 1997 12:42:45 -0700
- To: Mark_Day/CAM/Lotus@lotus.com, w3c-dist-auth@w3.org
I'm suprised that some people think that the reason that I've supported range locking is because GroupWise uses the feature, GroupWise does not. In the early days SoftSolutions did, but that is behind us. Basically, range locking is a useful method for implementing a fixed-length record store that provides the necessary functionality for small to medium document management systems (whether they do versioning or not). Some editing systems that use range locking do so because they access a fixed-length index of the document structure that provides all access to the document body. Range locking is used here to protect the specific portion of the document. In both cases you do not see the byte count changing except at the end of the fixed-length portion of the document or the DMS control file. Having been there, I suspect that there are systems out there that use range locking to provide this type of functionality. So now I'll put on my Novell hat. No, I don't need range locking. But I think we're being short sighted if we think that functionality such as range locking has no value to DAV. -src >>> <Mark_Day/CAM/Lotus@lotus.com> 02/21/97 08:54AM >>> I agree with Larry that it makes more sense in most cases to talk about section locks for the scenario of multiple authors wanting to manipulate different parts of the document. If your locks are on byte ranges, then the semantics (as I understand them) seem pretty unpleasant: 1. In the simplest approach, you can't change the size of the locked range unless you lock from the start of the range to the end of the document (thus effectively locking most of the document if what you're modifying is near the beginning of the document). 2. In a more complex approach, you can't safely re-lock a range using the same start & end points once you release the lock, because the actual byte numbering of that content in the document may have changed as others have inserted or deleted bytes from their ranges. Section locking also has this problem, but in a milder form: the problem arises as sections are added and removed, which one would expect to be much less common than adding and removing bytes. People who have more experience with byte-locking systems should feel free to correct me on these points if I have misunderstood. --Mark
Received on Friday, 21 February 1997 15:06:50 UTC