🚀 go-pugleaf

Hi,

I need to convert a date/time in a given timezone to a date/time in another
timezone.  While GetTimeZoneInformation() and
SystemTimeToTzSpecificLocalTime() might be useful functions, they are a far
cry from what is necessary to accomplish the task.

First, SystemTimeToTzSpecificLocalTime is a one way function
(UTC->localtime).  An inverse function is necessary to go from
localtime->UTC.  Though XP has such a function
(TzSpecificLocalTimeToSystemTime), it only exists on XP.  It is not
available on Win2K or NT.

Second, SystemTimeToTzSpecificLocalTime and TzSpecificLocalTimeToSystemTime
both require information about the target/source timezone.
GetTimeZoneInformation returns information about the system's current
timezone, but that's only useful if the system's current timezone happens to
be the source or the target timezone.

So, I have two questions:

1) How does one get timezone information about OTHER timezones?
2) Assuming it is possible to get the source/target timezone information,
what do you do when you are running on an OS that doesn't have
TzSpecificLocalTimeToSystemTime?

- Dennis