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Message-ID: <39571272-7ba3-4a95-880b-3f10a970baca@eisentraut.org>
Date: Mon, 12 Aug 2024 09:04:23 +0200
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Subject: Re: Remove support for old realpath() API
To: Thomas Munro <thomas.munro@gmail.com>
Cc: Heikki Linnakangas <hlinnaka@iki.fi>,
 pgsql-hackers <pgsql-hackers@postgresql.org>
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 <CA+hUKGLpmrr-vQHVWtMe-O=_AvS_CWWRJ+Y=UnGHd3P31S1RbQ@mail.gmail.com>
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From: Peter Eisentraut <peter@eisentraut.org>
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On 12.08.24 08:47, Thomas Munro wrote:
> On Mon, Aug 12, 2024 at 6:18 PM Peter Eisentraut <peter@eisentraut.org> wrote:
>> On 05.08.24 09:41, Heikki Linnakangas wrote:
>>> On 05/08/2024 09:12, Peter Eisentraut wrote:
>>>> The now preferred way to call realpath() is by passing NULL as the
>>>> second argument and get a malloc'ed result.  We still supported the
>>>> old way of providing our own buffer as a second argument, for some
>>>> platforms that didn't support the new way yet.  Those were only
>>>> Solaris less than version 11 and some older AIX versions (7.1 and
>>>> newer appear to support the new variant).  We don't support those
>>>> platforms versions anymore, so we can remove this extra code.
> 
> I checked this in the AIX 7.3 manual and the POSIX 2008 way does not
> appear to be mentioned there:
> 
> https://www.ibm.com/docs/en/aix/7.3?topic=r-realpath-subroutine
> 
> That's a bit confusing, or maybe there are just too many versioning
> systems to keep track of and I've made a mistake, because it looks
> like AIX 7.2.5+ has actual certification for Unix V7 AKA SUSv4 AKA
> POSIX 2008...  Or maybe the documentation is wrong and it does
> actually work.  I guess the IBM crew will be forced to look into this
> as they continue to work on their PostgreSQL/AIX patch, if it doesn't
> work...

Tom had tested this on and found that it does actually work on AIX 7.1 
and 7.3 but the documentation is wrong.