From: Tom Lane <tgl@sss.pgh.pa.us>
To: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
cc: Ranier Vilela <ranier.vf@gmail.com>,
        Laurenz Albe <laurenz.albe@cybertec.at>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: printf %s with NULL pointer (was Re: BUG #17098: Assert failed on
 composing an error message when adding a type to an extension being dropped)
In-reply-to: <3517180.1626280000@sss.pgh.pa.us>
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Comments: In-reply-to Tom Lane <tgl@sss.pgh.pa.us>
	message dated "Wed, 14 Jul 2021 12:26:40 -0400"
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Date: Wed, 14 Jul 2021 12:41:24 -0400
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I wrote:
> Interesting question, so I took a look:
> https://git.musl-libc.org/cgit/musl/tree/src/stdio/vfprintf.c#n593
>                     case 's':
> 			a = arg.p ? arg.p : "(null)";

BTW, the adjacent code shows that musl is also supporting glibc's
"%m" extension, so I imagine that they are endeavoring to be
compatible with glibc, and this goes along with that.  But that
just supports my larger point: printing "(null)" is clearly the
de facto standard now, whether or not POSIX has caught up with it.

			regards, tom lane