Re: pg11+: pg_ls_*dir LIMIT 1: temporary files .. not closed at end-of-transaction

Justin Pryzby <pryzby@telsasoft.com> writes:
> While working on a patch, I noticed this pre-existing behavior, which seems to
> be new since v11, maybe due to changes to SRF.

> |postgres=# SELECT pg_ls_dir('.') LIMIT 1;
> |WARNING:  1 temporary files and directories not closed at end-of-transaction

Hmm, actually it looks to me like pg_ls_dir has been broken forever.
The reason the warning didn't show up before v11 is that CleanupTempFiles
didn't bleat about leaked "allocated" directories before that
(cf 9cb7db3f0).

I guess we ought to change that function to use returns-a-tuplestore
protocol instead of thinking it can hold a directory open across calls.
It's not hard to think of use-cases where the existing behavior would
cause issues worse than a nanny-ish WARNING, especially on platforms
with tight "ulimit -n" limits.

            regards, tom lane