I've created packages.vbs to get the packages from a Windows system. Output
basically looks like this:

Name: Acrobat.com
Version: 1.6.65
Vendor: Adobe Systems Incorporated
Description: Acrobat.com

To do roughly the same for Linux (Well debain based Linux):

$ dpkg-query -W -f='Name: ${Package}\nVersion: ${Version}\nVendor: ${Vendor}\nDescription: ${Description}\n'

Which produces output like:

Name: alien
Version: 8.79ubuntu0.1
Vendor: 
Description: convert and install rpm and other packages
 Alien allows you to convert LSB, Red Hat, Stampede and Slackware Packages
 into Debian packages, which can be installed with dpkg.
 .
 It can also generate packages of any of the other formats.
 .
 This is a tool only suitable for binary packages.
 
I don't have a Redhat system to see how to get similar output from there. Then 
there's Sun, HP-UX, etc...