PG Bug reporting form <noreply@postgresql.org> writes:
> It would be good to add a flag to disable this feature, as some devices does
> not support seek calls, for example streaming devices such as a tape
> drive.
That seems like an extremely niche use-case, so I'm unexcited about adding
a switch for it. You can get the same results with a pipe, as your quoted
response from Red Hat support suggests.
Note that disabling seeking is not all that desirable in the first place,
as it will result (for -Fc output) in a dump file that is significantly
restrictive to restore performance, due to lack of data offset pointers.
You might really be best advised to rethink whether you want to write
directly to an unseekable device, rather than to a temp file you transfer
to tape later.
regards, tom lane