The following logical variables can be used to control the behavior of
   certain commands. They are fully described in the manual Guide to DIGITAL
   Test Manager for OpenVMS Systems or in the product Release Notes.

     DTM$DATE_FILTER_FIRST
     DTM$DATE_FILTER_MAX_YEAR
     DTM$DATE_FILTER_MIN_YEAR
     DTM$DATE_FILTER_STRING
     DTM$DATE_MASK_MAX_YEAR
     DTM$DATE_MASK_MIN_YEAR
     DTM$DELAY_TIMEOUT
     DTM$IGNORE_PROLOGUE_ERRORS
     DTM$OMIT_PRINTABLE_SCREENS
     DTM$RETAIN_RESULTS
     DTM$TIME_FILTER_NO_SPACE