A question, not an issue

[DrEmpiricism]

Is there a difference between using Microsoft.Dism.DismApi.CloseSession(Microsoft.Dism.DismSession) and Microsoft.Dism.DismSession.Close()?

If they both do the same thing, then I find the latter to be preferred within individual functions. Moreover, I have found that a closed DismSession handle will still return as 'IsClosed = false' until Microsoft.Dism.DismSession.Dispose() is called. Should both Close and Dispose be used?

[jeffkl]

The DismSession class implements SafeHandleZeroOrMinusOneIsInvalid which implements SafeHandle which is where the Close() method comes from.

https://github.com/jeffkl/ManagedDism/blob/d47995d874352dfbdaf53c6d68fa334e4d6c91d0/src/Microsoft.Dism/DismSession.cs#L14C39-L14C72

https://learn.microsoft.com/en-us/dotnet/api/system.runtime.interopservices.safehandle.close?view=net-10.0

I think both Close() and Dispose() call RelaseHandle() which is implemented by DismSession.

ManagedDism/src/Microsoft.Dism/DismSession.cs

Line 78 in d47995d

protected override bool ReleaseHandle()

My guess is that you can call Dispose() or Close() or put it in a using statement and it should all work as expected. I recommend a using:

using(DismSession session = DismApi.OpenOfflineSession(@"C:\mountedimage"))
{
}