Date: Thu, 22 Jul 2021 16:49:30 +0200 (CEST)
From: Fabien COELHO <coelho@cri.ensmp.fr>
To: Pavel Stehule <pavel.stehule@gmail.com>
cc: Peter Eisentraut <peter.eisentraut@enterprisedb.com>,
    "pgsql-hackers@lists.postgresql.org" <pgsql-hackers@lists.postgresql.org>
Subject: Re: psql - add SHOW_ALL_RESULTS option
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Hello,

> Minimally for PSQL_WATCH_PAGER, the pager should exit after some time, but
> before it has to repeat data reading. Elsewhere the psql will hang.

Sure. The "pager.pl" script I sent exits after reading a few lines.

> can be solution to use special mode for psql, when psql will do write to
> logfile and redirect to file instead using any (simplified) pager?

I do not want a special psql mode, I just would like "make check" to tell 
me if I broke the PSQL_WATCH_PAGER feature after reworking the 
multi-results patch.

> Theoretically, there is nothing special on usage of pager, and just you can
> test redirecting to file.

I do not follow. For what I seen the watch pager feature is somehow a 
little different, and I'd like to be sure I'm not breaking anything.

For your information, pspg does not seem to like being fed two results

   sh> PSQL_WATCH_PAGER="pspg --stream"
   psql> SELECT NOW() \; SELECT RANDOM() \watch 1

The first table is shown, the second seems ignored.

-- 
Fabien.