Shutdown the milter.
No connections will be accepted after this call.
||Called from any of the Callback routines
or any error-handling routines at any time.
||The smfi_stop routine prevents that new connections
will be accepted,
however, it does not wait for existing connections (threads) to terminate.
It will cause
smfi_main to return to the calling program,
which may then exit or warm-restart.
||Takes no arguement.
||smfi_stop always returns SMFI_CONTINUE. But note:
- Another internal routine may already have asked the milter to abort.
- Another routine may already have asked the milter to stop.
- There is no way to cancel the stop process once it has begun.