Looking For Suggestions

[Scott Rossi]

>> I've got a standalone that needs to run on Windows as a single 
>> instance
> (no
>> multiple instances of the same app).  I'm looking for suggestions on 
>> how
> to
>> prevent duplicate launches of the same app (the app may also be 
>> installed
> in
>> more than one location on the same machine).
>>
>> I'm familiar with the open apps function of the EXT DLL, but I'm 
>> trying to
>> avoid use of this since it makes my apps unstable.  I've also toyed 
>> with
> the
>> idea of writing an "app busy" message to the registry or a temp file 
>> on
> the
>> drive, but I can't figure out how to determine if the app that 
>> created the
>> message is running
>>
>
> I'm new to this MetaCard stuff, but it seems to me to be an easy 
> exercise in
> logic - if the busy message is there to be read, then another instance 
> of
> the program is running, and the running instance will clean up after 
> itself
> by removing the message before it exits?
>
> So if you find the temp variable, shut down.

Thanks for the suggestion. However, it doesn't take into account a 
situation where the app is unable to clean up after itself, such as 
after a system crash.  Then the system would be stuck with an "app 
busy" message and be unable to launch the app at all.  If there was a 
way to identify the app busy message with, for example, an addressable 
ID of the running app, your solution could work, but right now I can't 
see how this is possible.

This problem is a little more complicated than it seems. :-)

Regards,

Scott Rossi
Creative Director, Tactile Media