I asked in the dev email list without a response. So will also here.
I have observed a case when Kamaili debug module try to grab the lock on shutdown and not able to do it. As a result, the Kamailio process is stuck and not able to restart (dead lock).
To resolve such a case I want to utilize systemd watchdog [feature](https://www.freedesktop.org/software/systemd/man/sd_watchdog_enabled.html)
To use this feature I need to send sd_notify(3) with a message string of "WATCHDOG=1" from the main process. [Link](https://www.freedesktop.org/software/systemd/man/sd_watchdog_enabled.html)
According to systemd doc watchdog can be applied only to one process. [Link](https://www.freedesktop.org/software/systemd/man/sd_watchdog_enabled.html)
If the $WATCHDOG_USEC environment variable is set, and the $WATCHDOG_PID variable is unset or set to the PID of the current process, the service manager expects notifications from this process.
[Additional info](https://lists.freedesktop.org/archives/systemd-devel/2018-January/040185.htm...)
Could you suggest how to embed this systemd call to the main process? This will allow use `systemsd watchdog` feature.