pg_regress: Observe TMPDIR
Put the temporary socket directory under TMPDIR, if that environment
variable is set, instead of the hardcoded /tmp.
This allows running the tests if there is no /tmp at all (for example
on Windows, although running the tests with Unix-domain sockets is not
enabled on Windows yet). We also use TMPDIR everywhere else /tmp is
hardcoded, so this makes the behavior consistent.
Reviewed-by: Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
Discussion: https://www.postgresql.org/message-id/flat/
54bde68c-d134-4eb8-5bd3-
8af33b72a010@2ndquadrant.com