System V semaphore question

[Troy Cauble]

I have a question about cleaning up System V semaphores.

I see mention of an IPC_RMID command in the semctl(2) manpage.
Does this imply that the user must explicitly cleanup their
semaphores?  What if they don't?

If the process that created the semaphore exits, are the
appropriate kernel structures cleaned up/destroyed?
Is this any different for a IPC_PRIVATE semaphore?

Please respond via mail.
Thanks,
/tlc