Supplying password to pg_dump

I'm trying to incorporate a backup/restore facility into a Delphi
app, and I've run into trouble trying to get a password to pg_dump.
I'm developing using PostgreSQL 8.0 on my WinXP Pro laptop.

pg_dump is being executed by the Windows API function
ShellExecuteEx(). I've tried putting a pgpass.conf file into my
%appdata%\postgresql folder, as per the documentation, but it didn't
seem to make any difference.

Likewise, I tried adding a new user to PostgreSQL specifically for
the purpose of doing backups - this user had no password. Then I
added this line to pg_hba.conf:

host gfcflights gfcbak 127.0.0.1/32 trust

- but when running pg_dump I still get a password prompt.

What am I missing? I should mention that the final application will
be running on the same desktop machine as the DBMS - it's a small
management app for a club to which I belong, and network security
won't be an issue (there isn't one!) though accidental mischief-
making by club members might.

Thanks in advance!

--Ray O'Donnell

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Raymond O'Donnell http://www.galwaycathedral.org/recitals
rod(at)iol(dot)ie Galway Cathedral Recitals
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