I have a bunch of services (say
C9) that should only start after a service
S has completed its initialization and is fully running and ready for the other services. How do I arrange that with systemd?
In Ordering services with path activation and target in systemd it is assumed that service
S has a mechanism for writing out some sort of flag file. Assume here, in contrast, that I have full control over the program that service
S runs, and can add systemd mechanisms into it if needs be.