+/*
+ Returns > 0 if the service manager expects watchdog keep-alive
+ events to be sent regularly via sd_notify(0, "WATCHDOG=1"). Returns
+ 0 if it does not expect this. If the usec argument is non-NULL
+ returns the watchdog timeout in µs after which the service manager
+ will act on a process that has not sent a watchdog keep alive
+ message. This function is useful to implement services that
+ recognize automatically if they are being run under supervision of
+ systemd with WatchdogSec= set. It is recommended for clients to
+ generate keep-alive pings via sd_notify(0, "WATCHDOG=1") every half
+ of the returned time.
+
+ See sd_watchdog_enabled(3) for more information.
+*/
+int sd_watchdog_enabled(int unset_environment, uint64_t *usec);
+