Prevents jobs from being entered in the queue through PRINT or
    SUBMIT commands or as a result of requeue operations. To allow
    jobs to be entered, use the /OPEN qualifier. Whether a queue
    accepts or rejects new job entries is independent of the queue's
    state (such as paused, stopped, or stalled). When a queue is
    marked closed, jobs executing continue to execute. Jobs already
    pending in the queue continue to be candidates for execution.