PostgreSQL using .pgpass

[odyn_owl]

I want to make scripts that backup database, but pg_dump when execute asking for password.
I' wrotten here (http://www.postgresql.org/docs/8.1/interactive/libpq-pgpass.html) about password file, but this file didn't help me - script interept with error authentication failed for user "postgres".
May be somebody do that and can describe step by step what have to do.
thanks.

Server 6.06

[wasare]

export the environment variables PGUSER and PGPASSWORD

[tarvid]

Not wonderful but set

host all all 127.0.0.1/32 trust

as the first line and restart postgresql.

Might want to put it back afterwards.