SEMKEYINUSE, Semaphore key xxxx is already in use (possibly by an older version)
Run Time/MUPIP Error: This indicates that GT.M failed to create a semaphore. One possible cause is that a semaphore of ID xxxx already exists in the system and the number of semaphores in that semaphore set is different than the semget has attempted to create. If a new GT.M version increases the number of semaphores in the semaphore set, collision with an older GT.M version can cause this error.
Action: Check accompanying message(s) for additional information. Use the semstat2 tool to find detailed information about the existing semaphores in the system.