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Date:   Thu, 7 Mar 2019 19:20:43 +0000
From:   Joseph Myers <joseph@codesourcery.com>
To:     Lukasz Majewski <lukma@denx.de>
CC:     Zack Weinberg <zackw@panix.com>, Arnd Bergmann <arnd@arndb.de>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        GNU C Library <libc-alpha@sourceware.org>
Subject: Re: [Y2038] Question regarding support of old time interfaces beyond
 y2038
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On Thu, 7 Mar 2019, Lukasz Majewski wrote:

> > 1) We should be clear that most of these will continue to be supported
> > as C library interfaces even if they are not system calls.  Some of
> > them are obsolete enough and/or rarely used enough that we might not
> > bother (the older ways to set the system clock, for instance).
> 
> The question here is about the decision if even the old time APIs shall
> be supported on 32 bit systems which are going to be Y2038 proof (like
> the 'stime').

The glibc API should support the same set of functions both with and 
without _TIME_BITS=64.

I think it would be reasonable to obsolete the stime function in glibc 
(meaning turn it into a compat symbol, not available for linking new 
programs and not present at all for new architectures).  But that's 
orthogonal to supporting 64-bit times on 32-bit platforms in glibc.  If 
stime is obsoleted before (or in the same release as) that 64-bit time 
support, no 64-bit version of stime is needed in glibc.  If obsoleted in a 
later release, glibc would need to get a 64-bit version (and both versions 
would turn into compat symbols if the interface is obsoleted).

-- 
Joseph S. Myers
joseph@codesourcery.com