I believe it uses an algorithm to generate the GUID based on the KeyPath, but that's just from memory.
-- John Merryweather Cooper Senior Software Engineer | Integration Development Group | Continuing Development Jack Henry & Associates, Inc.® | Lenexa, KS 66214 | Ext: 431050 |jocoo...@jackhenry.com -----Original Message----- From: Pat Blair [mailto:p...@daburu.net] Sent: Sunday, March 29, 2015 9:12 AM To: wix-users@lists.sourceforge.net Subject: [WiX-users] How does heat maintain consistent GUIDs? I am curious to know how WiX keeps track of GUIDSs automatically generated for files when we use HeatDirectory. For example, I have a project with the following in my .wixproj file... <Target Name="BeforeBuild"> <PropertyGroup> <WixToolPath>C:\SourceControl\WiX39\</WixToolPath> </PropertyGroup> <HeatDirectory ToolPath="$(WixToolPath)" Directory="C:\users\me\Desktop\SourceFiles ComponentGroupName="MyComponentGroup" DirectoryRefId="INSTALLFOLDER" AutogenerateGuids="true" GenerateGuidsNow="false" SuppressFragments="true" SuppressRootDirectory="true" PreprocessorVariable="var.SourceFilesDir" OutputFile="Components.wxs" /> </Target> If I set AutogenerateGuids="true", my output file contains components like this: <Component Id="cmpA609F30B9E3AECCDEE4D779C8B7308ED" Guid="*"> <File Id="fil314398091041DF4762128892E7C98AA7" KeyPath="yes" Source="$(var.SourceFilesDir)\Sample1.txt" /> </Component> I note that Component/@Guid="*". After generating the .MSI, I open it with Orca and see that the ComponentId for each Component (for each file) is the same. If I change my HeatDirectory element so that AutogenerateGuids="false" and GenerateGuidsNow="true", the ComponentIds seem to change. If I understand correctly, this is how it should work and by using AutogenerateGuids, my installers can track a given file from install to install. I also think I understand that the GUIDs will remain the same so long as the file names and paths to which they are installed doesn't change, so this approach will let me do minor upgrades because the installers can tell that two versions of a file from two different installers are the same component because the ComponentIDs match. But what I'm wondering is: How are these consistent GUIDs that I get when I use AutogenerateGuids="true" remembered from build to build? Are they generated by some algorithm that will always produce the same GUID for a file with a given name installed to a given directory, or are they stored somewhere. And if they are stored somewhere, where are they stored? I'm hoping this isn't a dumb question, but I feel like I need to understand this before using the feature so I don't make mistakes based on an incomplete comprehension of what's happening behind-the-scenes. Many thanks. ------------------------------------------------------------------------------ Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ _______________________________________________ WiX-users mailing list WiX-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/wix-users NOTICE: This electronic mail message and any files transmitted with it are intended exclusively for the individual or entity to which it is addressed. The message, together with any attachment, may contain confidential and/or privileged information. Any unauthorized review, use, printing, saving, copying, disclosure or distribution is strictly prohibited. If you have received this message in error, please immediately advise the sender by reply email and delete all copies. ------------------------------------------------------------------------------ Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ _______________________________________________ WiX-users mailing list WiX-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/wix-users
