Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ukma!xanth!lazarus
From: lazarus@cs.odu.edu (Keith E. Lazarus)
Newsgroups: comp.editors
Subject: RE: multi-user editors.......
Summary: What is so terrible about the idea???
Keywords: why, how
Message-ID: <8583@xanth.cs.odu.edu>
Date: 21 Apr 89 05:34:45 GMT
Reply-To: lazarus@cs.odu.edu (Keith E. Lazarus)
Distribution: usa
Organization: Old Dominion University, Norfolk Va.
Lines: 76


this isn't going at all like i had hoped it would....
i think i'd better answer a couple of your questions.....


> Is this a joke?  What possible use would having several people
> editing the same file at the same time be? 

    no, its not a joke.....

    for a systems programming course i took this past semester, i was
    required to design and implement a utility for UNIX that did not 
    already exist.  while discussing possible topics for the project with
    my professor, he mentioned the idea of a multi-user editor.  
    since i'd been interested in the design of text-editors for a while, 
    I decided that this would be an interesting program to write......
    
    at the time, i didn't bother wondering about how necessary such an 
    editor would be, however, as time went on - i began to see some 
    of its strengths...
    
    personally - i don't feel such an editor is essential, it would just be
    a luxury.  (the only time that i can recall ever wishing for an editor
    that supports multiple users was last semester  when a friend and i were
    working on a project for one of our courses.  we had 15 minutes till it 
    was due and had to make a few modifications to two procedures.  
    he was responsible for one procedure, I was responsible for the 
    other and both were located in the same file.  Consequently, 
    he had to wait till I was finished and the phase ended up 
    being handed in late.....)  (note:  this was before i learned how 
    to change the 'last-accessed' time on files.. :-) )
    
    my editor isn't finished, however, it does support multiple users
    simultaneously performing most of the basic editing operations 
    on a single file (ie. insert line/character, delete line/character, 
    etc.....).  i expect that i'll have a reasonably useful implementation
    working by the end of the summer.
 
> How would you keep someone from changing the same information 
> that another is changing?   Who gets the last change?    

    i briefly described how i went about this in a posting i made earlier
    today ( i think... ).  if anyone wants a more detailed description of 
    the algorithm, let me know - i'd be more than happy to supply it.

--------

i'm really surprised at the reactions i've gotten when i've mentioned
this idea to people...  a very strange look and 2 questions:

            1) why would you want to allow that???  & 
            2) how can it be done??? 

i now realize that this is a <<<new>>> idea, however, I don't think that it is
too ridiculous.  i'm really surprised that nothing like this already exists.

i'm sure that at least one of y'all has wanted to make some changes to a file
at one time or another, but was unable to because someone else was already
editing that file.  granted, you could use the conventional technique to
solve this problem - go get a beer and come back later - i find this
somewhat inefficient, though.......

my original question still stands:

> Do any of y'all know of any full-screen editors that support multiple
> users editing a single file at one time???
 
i'd also still interesting in hearing about any possible uses for such
an editor...

                             k.e.l.
-- 
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  Keith E. Lazarus                     Department of Computer Science
  lazarus@xanth.cs.odu.edu             Old Dominion University  Norfolk, VA
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