A PFS is started for each FILESYSTYPE statement in the BPXPRMxx parmlib member whenever z/OS UNIX is started. The LFS and PFS exchange information during this initialization phase. Usually the PFS does not terminate.

The same ENTRYPOINT name may be specified on two or more FILESYSTYPE statements with different TYPE operands. This causes the same PFS to be started more than once. It is up to the PFS to allow this or to detect and reject it.