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Last I checked (which was about a decade ago) Windows doesn't call GetNextVariableName() - it just accesses variables on demand. We should probably handle that in a cleaner way.

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It seems like that is no longer the case. I was able to successfully retrieve a non-standard variable using the `UEFIv2` PowerShell module [1] (which is just a thin wrapper around the undocumented `NtEnumerateSystemEnvironmentValuesEx` function) without actually naming the variable in question.

To the untrained layman like me, this sounds like Windows actually is querying via `GetNextVariableName`, because UEFI doesn't seem to offer any other interfaces that aren't "get/set variable by name".

[1] https://www.powershellgallery.com/packages/UEFIv2

Ok, yes, sounds like it is in that case. Which means figuring out how Linux is doing this differently to Windows, sigh. The easiest validation is to boot Windows under qemu with a debug-enabled EDK2 build to trace the calls.

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