[wpkg-users] Excluding particular OS and architecture types from patch application

[Lukasz Zalewski]

Hi All,
This is a feature request, but i would be grateful for any workarounds 
to the current setup

I was wondering if it would be possible to add an option to package 
definition which will apply a patch to only  particular OS version(s) 
ignoring others, i.e. applying patches to XP only, or Windows 7 or 
Vista, maybe with the architecture as well
e.g.
<applyToOS condition="equal"  target="Windows XP" architecture="x86"/>
<applyToOS condition="lessorequal"  target="Windows Vista" 
architecture="AMD64" />
<applyToOS condition="greaterorequal"  target="Windows 7"/>


This summer we are planing to move one of the labs to Windows 7. There 
will be few applications that can be installed/make sense on one but not 
the other, for example
We have a custom msgina.dll that will only apply to XP but not to Vista 
or 7 - for Vista and 7 this will be replaced by custom 
CredentialsProvider module which in turn won't work on anything less 
than Vista
wpkg client for Windows 7 will be in the GroupPolicy form, for XP we 
will keep the existing wpkg client - unless there are plans to combine 
the two together ;)

For OS and application deployment we use MDT (Microsoft Deployment 
Toolkit) which allows to define which OS'es the application can be 
installed on - this is great for creating a generic groups of 
applications and letting the install process do the right thing.

At the moment i can think of the following workarounds, none of which 
are optimum or desired :(
1. Create a separate wpkg share, just for Windows 7, and use simlinks to 
link the common packages from existing (XP) one, missing the 
incompatible ones and adding new ones
2. Add checks that lookup the os release number in the registry and use 
it to determine if the software has been installed. This would only work 
in the initial stage and would not apply when the release number is 
incremented to flag the upgrade. Also it would claim that the package is 
installed (and it would place it in the local packages list) but in 
reality it would be not
3. Create custom scripts that run in the install and upgrade stages that 
check and permit the installation if the OS is appropriate. Again it 
would claim that the package is installed (and it would place it in the 
local packages list) but in reality it would be not.

Many Thanks

Luk