TPU$_SUCCESS       Initialization was completed successfully.
    TPU$_FAILURE       General code for all other errors during
                       initialization.
    TPU$_INSVIRMEM     Insufficient virtual memory exists for the
                       editor to initialize.
    TPU$_              No routine has been established to perform
    NOFILEROUTINE      file operations.
    TPU$_NONANSICRT    The input device (SYS$INPUT) is not a
                       supported terminal.
    TPU$_RESTOREFAIL   An error occurred during the restore
                       operation.
    TPU$_SYSERROR      A system service did not work correctly.