Date: Tue, 19 Mar 2024 21:27:23 -0400
From: Bruce Momjian <bruce@momjian.us>
To: Thomas Munro <thomas.munro@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Christophe Pettus <xof@thebuild.com>,
	Andrew Dunstan <andrew@dunslane.net>,
	Wolfgang Walther <walther@technowledgy.de>,
	PostgreSQL Bugs <pgsql-bugs@lists.postgresql.org>
Subject: Re: Regression tests fail with musl libc because libpq.so can't be
 loaded
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On Wed, Mar 20, 2024 at 02:12:54PM +1300, Thomas Munro wrote:
> On Wed, Mar 20, 2024 at 12:54 PM Bruce Momjian <bruce@momjian.us> wrote:
> > So this would truncate the process title on all Linux that have an LD_
> > environment entry, even those without musl?
> 
> Yep.  How long is /proc/XXX/cmdline (check with wc -c /proc/...) in a
> postmaster near you?  You'd always get that much, plus as much of

	$ cat /proc/2000/cmdline |wc -c
	30

> /proc/XXX/environ as we can find before you reach LD_XXX=, which on a
> typical system would, I guess, usually be never.  If it's a problem
> you could try to arrange for LD_ XXX to come later in environ[].  What
> I observe is that they seem to get copied in backwards, wrt the
> environment exported by the parent, so if you set DUMMY=XXXXXXXX just
> before starting the process it'll make sacrificial space in the right
> place (but I'm not sure where that effect is coming from so don't
> quote me).

I am just cautious about changing behavior on our most common platform
for a libc library I have never heard of.

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EDB                                      https://enterprisedb.com

  Only you can decide what is important to you.