[GRASSLIST:994] Re: g.select.pg problem: list OK but refuse to select available database

[tlaronde at polynum.org]

En réponse à Glynn Clements <glynn.clements at virgin.net>:

> 
> Note that the g.select.pg program in 5.0.2 (and earlier) doesn't allow
> you to "undefine" a host. Once you use "g.select.pg host=...", all
> subsequent connections will be via TCP/IP. You can select a different
> host, but you can't revert to Unix domain sockets.
> 
> To revert to using a Unix domain socket to connect to a local
> postmaster process, you have to manually delete the PG_HOST entry from
> the $GISRC file (typically ~/.grassrc5).
> 
> This is fixed in the CVS HEAD version, and should be fixed in 5.0.3.

Thanks for the tip! What had and still puzzle me is that even when the PG_HOST
is set and postmaster not accepting TCP/IP connections, the listing of the
databases succeeds but the connection not (the latter is normal, the former
may be some side effect). Since there is nothing obvious in the g.select.pg
code (both listdb and getdbname use the same functions) it may be an
artefact of the PostgreSQL API.