Stack file organisation

Scott Raney raney at metacard.com
Wed Dec 18 12:50:01 EST 2002


On Wed, 18 Dec 2002 Richard Gaskin <ambassador at fourthworld.com> wrote:

> Ted wrote:
> 
> >>> 
> > Has anyone had a corrupt stack in Rev? I presume setting the
> > cantModify would prevent anything like this.
> > <<
> > 
> > 
> > I've had one corrupt stack in Rev. It was in the development environment, and
> > the cantModify was false.
> 
> How long ago was this?
> 
> The only corruption I've experienced with the MetaCard file format was a
> control-level corruption (bad button record) back in '97.
> 
> Such thing are very rare in Rev/MC, mostly due to the RAM-based
> architecture.
> 
> Note that discussions of corruption are largely limited to programs that
> page large structures from disk (like cards records in HyperCard and
> SuperCard or database records in FileMaker).
> 
> With everything stored in RAM, Rev has a lot less overhead managing the
> swapping from disk to cache and back again.  Accordingly, cases of actual
> corruption in a Rev stack are extremely rare.  I'd never even heard of one
> in Rev or MC in the last four years until I read this thread.

Nor have we, and so I'd be very surprised if the problem wasn't what
we call a "short save".  This happens when the program crashes during
a save, and so the resulting file doesn't have all the data in it.  In
this case, there will always be a file with a ~ as the last character
that has the previous version of the stack in it.  Meaning you lose
all your edits since that last save, but nothing else.  Just rename
that file, and you're back in business.

And except for under MacOS, which tends to have lots of problems with
memory management and inter-application conflicts, crashes like this
should be extremely rare.  If you've got something that you can
reproduce, by all means send in a bug report so that we can make it
even rarer ;-)
  Regards,
    Scott

> -- 
>  Richard Gaskin 
>  Fourth World Media Corporation
>  Developer of WebMerge 2.1: Publish any database on any site
>  ___________________________________________________________
>  Ambassador at FourthWorld.com       http://www.FourthWorld.com
>  Tel: 323-225-3717                       AIM: FourthWorldInc

********************************************************
Scott Raney  raney at metacard.com  http://www.metacard.com
MetaCard: You know, there's an easier way to do that...




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