Displays the following summary information for each cache file
    block (CFB): CFB address, cache volume block (CVB) address,
    access count, active I/O count, and file ID.

    /BRIEF is incompatible with /EXTENTS, /FULL, and /STATISTICS.

    If the file specification is available in LIB$FID_TO_NAME(), it
    is displayed; otherwise, the file ID is displayed.

                                   NOTE

       Because the volume is accessed through its logical name,
       if two volumes are mounted that have the same logical
       name (for example, one mounted /SYSTEM and one mounted
       privately, which results in the same logical name in two
       different access-mode logical name tables), the incorrect
       file specification might be displayed.