From: Tom Lane <tgl@sss.pgh.pa.us>
To: Christoph Moench-Tegeder <cmt@burggraben.net>
cc: Anders Kaseorg <andersk@mit.edu>, Daniel Gustafsson <daniel@yesql.se>,
        Kyotaro Horiguchi <horikyota.ntt@gmail.com>, alvherre@alvh.no-ip.org,
        pgsql-hackers@lists.postgresql.org
Subject: Re: [PATCH] Prefer getenv("HOME") to find the UNIX home directory
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Comments: In-reply-to Christoph Moench-Tegeder <cmt@burggraben.net>
	message dated "Sun, 09 Jan 2022 22:51:37 +0100"
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Christoph Moench-Tegeder <cmt@burggraben.net> writes:
> ## Tom Lane (tgl@sss.pgh.pa.us):
>> Given the POSIX requirements, it's basically impossible to believe
>> that there are interesting cases where $HOME isn't set.

> When I look at a random Debian with the usual PGDG packages, the
> postmaster process (and every backend) has a rather minimal environment
> without HOME. When I remember the code correctly, walreceiver uses
> the functions from fe-connect.c and may need to find the service file,
> a password file or certificates. If I'm correct with that, requiring
> HOME to be set would be a significant change for existing "normal"
> installations.
> What about containers and similar "reduced" environments?

Isn't that a flat out violation of POSIX 8.3 Other Environment Variables?

    HOME
        The system shall initialize this variable at the time of login to
        be a pathname of the user's home directory. See <pwd.h>.

To claim it's not, you have to claim these programs aren't logged in,
in which case where did they get any privileges from?

			regards, tom lane