Re: pgsql: Enable TAP tests of pg_receivewal for ZLIB on Windows, take thre

On Thu, Aug 05, 2021 at 11:49:01AM -0400, Andrew Dunstan wrote:
> Yeah, pretty much. I wonder what zlib API the pg_receivewal tests are
> tickling that other tests have not?

The main issue is that this is the first test suite stressing directly
zlib internals, as we only use gzread(), gzwrite() and gzflush()
within pg_dump/ and pg_basebackup/. And there is currently no
coverage of pg_dump --compress. My guess is that nobody tackled this
issue because of the need to make the tests conditional depending on
the compilation options.

Saying that, I recall two error patterns from this thread's
experience thanks to the specific error messages we have in
pg_receivewal for the handling of the WAL segments:
- gzopen(), followed by gzwrite() failing on EACCES.
- gzopen(), followed by gzflush() failing.
--
Michael