Why is the focus on documentation entries when the real work should be on trying to make this function to work on all platforms?

I understand that Windows's implementation of strftime() defines %z and %Z to return the same thing, but timezone information is still available in other ways. For example, _get_timezone() returns the offset in seconds between localtime and UTC. I don't have VC++ 2010 installed so I can't test it but this seems like a fairly simple thing to fix. Just take that result and multiply.

ref: https://msdn.microsoft.com/en-us/library/38wx0s70%28v=vs.100%29.aspx