I'm writing a small app to compare date-time stamps of files over the Internet, and I need some way to convert them to a universal format such as GMT or UTC so the times will be compared properly.

Does anyone know of a function to do this or any API calls that will get the job done? The only thing I've seen so far is a [MAPI 1.0 Time Zone] section in WIN.INI, but all it has is a bunch of entries in hex that I'd have to convert to use. I'm sure there are similar entries in the registry, but there's no way I'm just going to wade through that without knowing what I'm looking for. =)

I work for a very small company that only has to work with clients in the U.S., so I only have to support a few time zones if I have to do a complicated hack (taking the timezone values from WIN.INI and doing a SELECT CASE on them to get a GMT-5:00, GMT-6:00, etc...). And no, I'm not forgetting about Daylight Savings Time either... *grin*

This is more fun than I'd like to have at work... Please help if you know _anything_ that could come in handy. Thanks.