Please exit with zero status upon receiving SIGTERM

[bjornfor]

Services run under systemd receive SIGTERM when it's time to stop the service. dictd doesn't seem to handle SIGTERM and exits with status 143 (128 + 15 SIGTERM). Since the exit code is non-zero, systemd marks the service as failed. I'd like dictd to exit with zero status in this case, to not falsely report errors to the service manager.

Workaround: tell systemd/dictd.service that the SIGTERM exit code is success: SuccessExitStatus=143.