+ FDSTORE=1 Store the file descriptors passed along with the
+ message in the per-service file descriptor store,
+ and pass them to the main process again on next
+ invocation. This variable is only supported with
+ sd_pid_notify_with_fds().
+
+ WATCHDOG_USEC=...
+ Reset watchdog_usec value during runtime.
+ To reset watchdog_usec value, start the service again.
+ Example: "WATCHDOG_USEC=20000000"
+