Peter Eisentraut <peter_e(at)gmx(dot)net> writes:
> The current behaviour of libpq is to use Unix sockets whenever the host
> parameter (PGHOST or setdbLogin argument) is NULL/unset.
> Could we extend that to also use Unix sockets if the parameter is set but
> empty?
Seems reasonable, since the current behavior in that case is useless:
$ PGHOST='' psql
psql: connectDBStart() -- unknown hostname:
$
Backwards compatibility with that doesn't seem necessary ...
regards, tom lane