When checking if a listener is active or not in Oracle:

lsnrctl status

This command should return something similar to the following. Check-out the Services summary:

Services Summary…
Service “PLSExtProc” has 1 instance(s).
Instance “PLSExtProc”, status UNKNOWN, has 1 handler(s) for this service…
Service “domain.name.com” has 1 instance(s).
Instance “dmcl”, status READY, has 3 handler(s) for this service…