Message-ID: <726eece8-6e9d-9013-0e4a-a1f9e40c09b3@iki.fi>
Date: Mon, 12 Jun 2023 11:48:14 +0300
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Subject: Re: check_strxfrm_bug()
To: Thomas Munro <thomas.munro@gmail.com>,
 pgsql-hackers <pgsql-hackers@postgresql.org>
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From: Heikki Linnakangas <hlinnaka@iki.fi>
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On 12/06/2023 01:15, Thomas Munro wrote:
> There are still at least a couple
> of functions that lack XXX_l variants in the standard: mbstowcs() and
> wcstombs() (though we use the non-standard _l variants if we find them
> in <xlocale.h>), but that's OK because we use uselocale() and not
> setlocale(), because uselocale() is required to be thread-local.

Right, mbstowcs() and wcstombs() are already thread-safe, that's why 
there are no _l variants of them.

> The use of setlocale() to set up the per-backend/per-database
> default locale would have to be replaced with uselocale().
This recent bug report is also related to that: 
https://www.postgresql.org/message-id/17946-3e84cb577e9551c3%40postgresql.org. 
In a nutshell, libperl calls uselocale(), which overrides the setting we 
try set with setlocale().

-- 
Heikki Linnakangas
Neon (https://neon.tech)