The Create a Semaphore routine creates and initializes a
    semaphore with a waiting queue, and returns the semaphore
    identifier. You use the semaphore identifier to perform all
    operations on that semaphore.

    Format

      PPL$CREATE_SEMAPHORE  semaphore-id [,semaphore-name]

                            [,semaphore-maximum] [,semaphore-initial]