[Qt-interest] New Date and Time Features in Qt5?

[Thiago Macieira]

On Monday, 30 de May de 2011 22:56:33 David Ching wrote:
> I could be writing a UI that shows the user their time zone and whether or
> not DST is in effect or not.  When showing user the timezone, they expect to
> always see the same one regardless of whether DST is in effect or not.  For
> example, I am in San Francisco, I expect to see Pacific Time as UTC-8, even
> though currently DST is in effect, and thus current time is only 7 hours
> behind UTC.  I do not expect to see the UI show me UTC-7 in this case,
> which is the only thing possible given the calculations that can currently
> be performed with QDateTime.

Well, I do. I certainly expect software to say that it's in GMT+2 when Central 
Europe enters DST. In fact, all my email is sent like that (this email should 
say +0300 because I am in Finland).

> I have another case where I need to query the current UTC time (current
> QDateTime provides this OK) and also the offset in minutes of the local
> timezone compared to UTC.  This offset should not take into account DST (not
> possible in Qt now).  These two info is sent via serial port to FTDI chip
> on a USB device to set its current time.  It tracks DST itself and applies
> it, that's why the offset I send should not include DST.

That sounds... wrong. Either the communication happens in local time or in UTC 
time. Happening in "the timezone we would be in if we didn't have DST" sounds 
just broken to me.

-- 
Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org
  Senior Product Manager - Nokia, Qt Development Frameworks
      PGP/GPG: 0x6EF45358; fingerprint:
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