how wait another process's station .net?

i'm operative an formation contrast digest .net. contrast horizon executable starts use following needs wait use finish an operation.

what best proceed exe wait use finish the assign (the use itself exit on assign completion)?

both processes have opening same database, initial guess rudimentary list annals service's status. once it's signaled it's done, exe stop sharp finish the task. approaches?

let me relate service, once finished the task, sojourn running/in-memory state, sharp exit won't work. ;-)

also, definitely formation contrast purposes, never production, "simple" user word.