Creates global DCL symbols that contain the size information
    about the volume.

    EFICP$CLUSTER_SIZE - size of a disk cluster

    EFICP$FREE_BYTES - Number of bytes available for use on disk

    EFICP$FREE_CLUSTERS - Number of free clusters

    EFICP$TOTAL_BYTES - Total amount of bytes on disk

 EFI$CP> SHOW FAT EFI:

 Current Contents of FAT16 File Allocation Table:

 Dump of disk map:  key: Bad(?); Reserved(=); Free(-); Occupied(+); EOC(*)

 0x0000: ==-*****++++++++++++++++++++++++
    .
    .
    .
 0x1660: ++++++++++++++++++++++++++++++++
 0x1680: ++++*******---------------------
         Block of 1814 free FAT entries suppressed
 0xf960: --------------------------

 FAT size:                        250 sectors, 128000 bytes
 FAT array size:                  64000
 FAT bytes per sector:            512
 FAT sectors per cluster:         4
 FAT bytes per cluster:           2048
 FAT clusters available:          63866
 FAT total disk space:            130797568 bytes
 FAT reserved cluster count:      2
 FAT first free cluster:          2
 FAT free cluster count:          58096
 FAT bytes available on disk:     118980608

 EFI$CP>

 EFI$CP> sho fat/noblock efi:

 Current Contents of FAT16 File Allocation Table:

 FAT size:                        250 sectors, 128000 bytes
 FAT array size:                  64000
 FAT bytes per sector:            512
 FAT sectors per cluster:         4
 FAT bytes per cluster:           2048
 FAT clusters available:          63866
 FAT total disk space:            130797568 bytes
 FAT reserved cluster count:      2
 FAT first free cluster:          2
 FAT free cluster count:          58096
 FAT bytes available on disk:     118980608

 EFI$CP>

 EFI$CP> sho fat/nolog/symbols efi:
 EFI$CP> Exit
 $ sho sym eficp$*
   EFICP$CLUSTER_SIZE == "2048"
   EFICP$FREE_BYTES == "118980608"
   EFICP$FREE_CLUSTERS == "58096"
   EFICP$TOTAL_BYTES == "130797568"
 $