Re: pgsql: Consistently test for in-use shared memory.

On Mon, Apr 15, 2019 at 09:01:45PM -0400, Tom Lane wrote:
> Noah Misch <noah@leadboat.com> writes:
> >> Perhaps I should write the 'SELECT 1 + 1' to a regular file and redirect input
> >> from that file.
> 
> Actually ... we don't need to run a query at all do we?

No.  We expect never to run one; it was there for the unexpected case of
"postgres --single" startup succeeding.  I pushed a change to close the stdin
of "postgres --single" instead of writing to it.  I probably worried that
"postgres --single" would not tolerate that, but it seems to.