From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,80b3e504140e89fd X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2002-06-20 13:03:06 PST Path: archiver1.google.com!news1.google.com!newsfeed.stanford.edu!canoe.uoregon.edu!hammer.uoregon.edu!skates!not-for-mail From: Stephen Leake Newsgroups: comp.lang.ada Subject: Re: Config_Files proposal Date: 20 Jun 2002 15:54:21 -0400 Organization: NASA Goddard Space Flight Center (skates.gsfc.nasa.gov) Message-ID: References: <3D0FAC67.A4861809@san.rr.com> <3D10B6B1.AFE9D4E8@san.rr.com> <3D10E046.E604231D@san.rr.com> <3D1204B5.4620F160@san.rr.com> NNTP-Posting-Host: anarres.gsfc.nasa.gov Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: skates.gsfc.nasa.gov 1024603320 7356 128.183.220.71 (20 Jun 2002 20:02:00 GMT) X-Complaints-To: usenet@news.gsfc.nasa.gov NNTP-Posting-Date: 20 Jun 2002 20:02:00 GMT User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.2 Xref: archiver1.google.com comp.lang.ada:26514 Date: 2002-06-20T20:02:00+00:00 List-Id: Darren New writes: > Stephen Leake wrote: > > Let's see. You have two instances of "text_edit", sharing one config > > file. That is explicitly forbidden by requirement 1. > > Then requirement one should speak of concurrent use, rather than > simultaneous use. :-) Yes, that is better. > > This is a race condition. Suppose two processes happen to start a > > "flush" operation "at the same time"? Whichever goes last wins. > > That would be simultaneous use. ;-) Ok, neither simultaneous nor concurrent use is supported. > > If you feel that makes Config_Files totally useless, I guess we > > can talk about removing requirement 1 and see if we can come up > > with locking semantics to fix it. But I'd rather not, especially > > since the registry and gconf have already done that. > > I don't know that we need locking semantics. I just thought it would be easy > to apply the changes and merge them appropriately. For that matter, you're > going to have a similar problem if you have two threads in the same program > doing this. Yes, but Ada programmers are supposed to be aware of things like that. I guess it wouldn't hurt to mention it. > Certainly it at least has to be made clear in the specs. yes. > > > OK. I'd misinterpreted, thinking you meant only one process > > > could read or write at a time, rather than only one process > > > could be using a configuration at a time. > > > > Ok, I guess I need to make that clearer. I thought one implied the > > other :). Your example is more complex than I had in mind; I'll try to > > include something like it in the final rationale document. > > OK. I'm just trying to have ideas about problems before anyone puts a lot of > work into something, only to find out that the end-users find it too > unintuitive to use. Yes, and I do appreciate that. > Something like "list API" is one thing, since only programmers who > read the instructions are going to see that. Something like a config > file where the user can set configurations is another thing. Perhaps > it's worth having an option to create a lock file of some sort. Only if we can define it well. > > But I want _you_ to pick a format, so we can get consensus. Hmm. > > You said above either is ok; I guess that counts as consensus for > > the Java property format. > > Yes. I've been pushing towards something where there are minimal syntactic > interdependencies between keys, rather than something like XML. I'm more > concerned about precise semantics than about the niggly details of the file > format, tho. Ok, I'll put you on the Java side. -- -- Stephe