Re: LibPQ doesn't say host=* translates to localhost

David G. Johnston <david.g.johnston@gmail.com>

From: "David G. Johnston" <david.g.johnston@gmail.com>
To: Francisco Olarte <folarte@peoplecall.com>
Cc: PostgreSQL Bug List <pgsql-bugs@lists.postgresql.org>
Date: 2024-06-28T16:11:17Z
Lists: pgsql-bugs
On Fri, Jun 28, 2024 at 12:48 AM Francisco Olarte <folarte@peoplecall.com>
wrote:

> On Thu, 27 Jun 2024 at 21:57, David G. Johnston
> <david.g.johnston@gmail.com> wrote:
> > The documentation [0] doesn't say this should work and general
> networking knowledge leads me to believe it wouldn't [1].
> >
> > PGHOST='*' psql postgres
> > psql (17beta1)
> > SSL connection (protocol: TLSv1.3, cipher: TLS_AES_256_GCM_SHA384,
> compression: off, ALPN: postgresql)
> > Type "help" for help.
> >
> > postgres=# \conninfo
> > You are connected to database "postgres" as user "davidj" on host "*"
> (address "127.0.0.1") at port "5432".
> > SSL connection (protocol: TLSv1.3, cipher: TLS_AES_256_GCM_SHA384,
> compression: off, ALPN: postgresql)
> >
> > David J.
> >
> > [0]
> https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-PARAMKEYWORDS
> >
> > [1]
> > ping *
> > ping: src: Temporary failure in name resolution
>
> Bad quoting, PGHOST=¡*', single quoted, but ping *, unquouted, with an
> error message which hints at <<echo ping *>> giving back <<ping src
> ....>>
>
> Bug may be real, but ping '*' could give some better data for debugging.
>
>
Good catch.

ping '*'
ping: *: Name or service not known

This is Ubuntu.

I'm fine with not documenting this if we are delegating to some underlying
library that makes the behavior platform-specific (though maybe document
that...even though it now seems obvious to me in retrospect).  I just
thought since ping didn't work we were doing something in between to avoid
the issue.

David J.