I wrote:
> richard coleman <rcoleman(dot)ascentgl(at)gmail(dot)com> writes:
>> I have checked and the postgres user can read/write to the file just fine.
> Check that again. Check lookup permission on all the directories in
> the path, too.
BTW, if you're on a selinux-enabled system (most Red-Hat-based
distros), you need to check file contexts too. Under selinux,
it's not uncommon for a daemon process to have fewer privileges
than the "same" user running an interactive session.
regards, tom lane