Record locking

[Kenneth Brody]

"Jay R. Ashworth" wrote:
> 
> On Wed, Mar 31, 2004 at 12:15:30PM -0500, John Esak wrote:
> > I understand what you are saying... and it probably _does_ have to do with
> > Windows somewhere somehow... but filePro is working with in-memory values...
> > not those written to disk... so if you say:
> >
> >       num=ctl(1) and then refer to it later... filePro is using its own copy
> > in memory of that value... it doesn't matter _when_ it gets written to
> > disk... it is going to be written in the proper sequential order of
> > things... or at least that is the way it is supposed to work... :-)
> 
> Unless two workstations both go after a copy at the same time.

Which is why you need to protect lookups which are to be modified.

> If the code is written wrong, it's possible for them to both get the
> same number; race conditions are a bitch.

I wonder what would happen if 5.1 made it a fatal error to modify an
unprotected lookup?  ;-)

-- 

+---------+----------------------------------+-----------------------------+
| Kenneth |     kenbrody at spamcop.net      | "The opinions expressed     |
|    J.   |    http://www.hvcomputer.com     |  herein are not necessarily |
|  Brody  |      http://www.fptech.com       |  those of fP Technologies." |
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