Re: tzset: add native Windows workaround

[Marco Atzeri]

On 03/05/2017 17:24, Paul Eggert wrote:
> On 05/03/2017 04:31 AM, Ken Brown wrote:
> > > Perhaps the Cygwin folks could be talked into changing an unset TZ to
> > > mean "ask the Windows Control Panel".
> >
> > This seems to already be happening.  Here's what I see on my Cygwin
> > system:
> >
> > $ echo $TZ
> > America/New_York
> >
> > $ date +'%Y-%m-%d %H:%M:%S %z (%Z)'
> > 2017-05-03 07:29:03 -0400 (EDT)
> >
> > $ TZ= date +'%Y-%m-%d %H:%M:%S %z (%Z)'
> > 2017-05-03 11:29:14 +0000 (GMT)
> >
> > $ unset TZ
> >
> > $ date +'%Y-%m-%d %H:%M:%S %z (%Z)'
> > 2017-05-03 07:29:30 -0400 (EDT)
>
> Hmm, but is the last output line because the Windows Control Panel
> specifies New York time, or because there is a 'localtime' file
> maintained by Cygwin that specifies New York time? I'm guessing the
> latter, since that's what glibc does. The former is what Bruno is asking
> for.

It is linked to Windows Control Panel, changing it to different
settings I have in the same Cygwin session :

 $ unset TZ

 $ date +'%Y-%m-%d %H:%M:%S %z (%Z)'
2017-05-03 17:51:52 +0200 (WEDT)

 $ date +'%Y-%m-%d %H:%M:%S %z (%Z)'
2017-05-03 18:53:26 +0300 (TST)

 $ date +'%Y-%m-%d %H:%M:%S %z (%Z)'
2017-05-03 22:53:46 +0700 (SEAST)

Regards
Marco