Wait, I reread what Jacque posted. Is the data being saved in the web app 
itself?? Is that a good idea? 

Bob S


> On Aug 8, 2025, at 8:03 AM, Bob Sneidar via use-livecode 
> <use-livecode@lists.runrev.com> wrote:
> 
> Race conditions can be worse than that. Person A makes changes, person B also 
> makes changes, person B saves his changes before person A, person A saves his 
> changes overwriting person B changes, person B does not know about it. The 
> solution to that is to set a counter that gets read when starting an edit, 
> then check to ensure the counter is the same before saving. Upon saving 
> increment counter by 1 with a rollover at max value. Another thing that can 
> be done is to set the counter to the maximum when starting an edit, so that 
> subsequent edits will know the form has been locked.
> 
> Bob S
> 
> 
> On Aug 7, 2025, at 3:31 PM, J. Landman Gay via use-livecode 
> <use-livecode@lists.runrev.com> wrote:
> 
> A web app runs in a browser; that's the main difference. LC Create makes web 
> apps.
> 
> It occurred to me that you will need to deal with race conditions, whether 
> the app is a web app or a standalone that reads a stack from a server. A race 
> condition is when more than one person is using the app at the same time. One 
> person saves changes and it is uploaded to the server. If another person is 
> using the app simultaneously and then saves their own changes, it will 
> overwrite the first person's changes. To deal with that you'll need to set 
> some sort of flag that the standalone checks before sending changes to the 
> server. Usually the flag is just a plain text file. If the flag is set to 
> true, the app needs to wait until the flag is false before redownloading the 
> changed stack, applying the second user's changes, and then uploading the 
> revised stack to the server again.
> 
> I've never had to deal with that since all my own work has been static and 
> the working stack has always been read-only (mostly educational materials.) I 
> remember that Andre was very cautious about race conditions and posted his 
> technique on the mailing list some years ago but unfortunately I didn't save 
> it.
> 
> --
> Jacqueline Landman Gay | 
> jac...@hyperactivesw.com<mailto:jac...@hyperactivesw.com>
> HyperActive Software | 
> http://www.hyperactivesw.com<http://www.hyperactivesw.com/>
> On August 7, 2025 4:12:28 PM Craig Newman via use-livecode 
> <use-livecode@lists.runrev.com<mailto:use-livecode@lists.runrev.com>> wrote:
> 
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