Date: Fri, 15 Mar 2019 08:01:12 -0700
From: Noah Misch <noah@leadboat.com>
To: Dagfinn Ilmari =?iso-8859-1?Q?Manns=E5ker?= <ilmari@ilmari.org>
Cc: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>,
	pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: libpq environment variables in the server
Message-ID: <20190315150112.GD2607362@rfd.leadboat.com>
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 <20190303080620.GA1750246@rfd.leadboat.com>
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On Fri, Mar 15, 2019 at 10:06:29AM +0000, Dagfinn Ilmari Mannsåker wrote:
> Peter Eisentraut <peter.eisentraut@2ndquadrant.com> writes:
> 
> > On 2019-03-15 05:00, Noah Misch wrote:
> >> I consider the following style more idiomatic:
> >> 
> >>  {
> >>      local %ENV;
> >>      delete $ENV{PGAPPNAME};
> >>      ...
> >>  }
> >
> > That doesn't work because the first line clears the entire environment.
> 
> The solution to that is to do 'local %ENV = %ENV;', to assign a copy of
> the original to the localised variable.

That's the right thing, not what I wrote.  We use that in
src/bin/initdb/t/001_initdb.pl.