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From: Ruediger Meier <sweet_f_a@gmx.de>
To: kerolasa@gmail.com
Subject: Re: [PATCH] hwclock: remove UTC-0 localization hack
Date: Tue, 12 Jul 2016 16:23:04 +0200
Cc: J William Piggott <elseifthen@gmx.com>,
        "util-linux" <util-linux@vger.kernel.org>
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On Tuesday 12 July 2016, Sami Kerola wrote:
> On 11 July 2016 at 21:23, J William Piggott <elseifthen@gmx.com> 
wrote:
> > We use mktime(3) for portability.
> >
> > http://www.gnu.org/software/libc/manual/html_mono/libc.html#index-t
> >imegm
> >
> > Portability note: mktime is essentially universally available.
> > timegm is rather rare. For the most portable conversion from a UTC
> > broken-down time to a simple time, set the TZ environment variable
> > to UTC, call mktime, then set TZ back.
>
> I don't think hwclock(8) is portable. It has ioctl(2) calls, and
> such.

But there are non-gnu libc's for Linux.

cu,
Rudi