[wpkg-users] wpkg - how to upgrade between different products like 'firefox 3' to 'firefox 4'?

[Malte Starostik]

Am Donnerstag, 1. September 2011, 10:22:05 schrieb Urs Rau (UK):
> I have not found a way to do it as the main executable and the uninstall
> wpkg is using is all using the identically named files for checks etc, so
> the uninstall of the lower or earlier version can inadvertently uninstall
> the newer or higher version as it does it's checks it finds the, now
> newer, exe is still present.
> 
> Obviously the mistake and big error was to have multiple wpkg packages all
> referencing the same executables. (i.e. firefox.exe and uninstall.exe). We
> should have only ever had a single firefox pkg called firefox.

We only have a single "firefox" package, but this still applies I guess.  There 
is one principle *all* our packages follow and that is that the combination of 
checks MUST (as per RFC 2119) only succeed for this very version of the 
software.  For firefox this means, there is this check as well as one for the 
firefox.exe file:

<check type="uninstall" condition="versionequalto" path="Mozilla Firefox 
\d+(\.\d+)* \(x86 de\)" value="5.0.1"/>

- be sure to change the language in the "path" as needed.  At least the newer 
firefox versions' firefox.exe also carries a version resource, so be sure to use 
"versionequalto" for the exe check as well.  If all else fails, a package can 
still create a flag file or registry key including version information just for 
checks.
This way, a check will simply fail if another version is installed.  If you 
have distinct packages for different versions, just make sure that no host 
includes more than one of them in its profile(s) at any time unless the specific 
software allows side-by-side installation of multiple versions.

Cheers,
Malte