INT 18 - DISKLESS BOOT HOOK (START CASSETTE BASIC)
Desc:   called when there is no bootable disk available to the system
Notes:  only PCs produced by IBM contain BASIC in ROM, so the action is
          unpredictable on compatibles; this interrupt often reboots the
          system, and often has no effect at all
        network cards with their own BIOS can hook this interrupt to allow
          a diskless boot off the network (even when a hard disk is present
          if none of the partitions is marked as the boot partition)
SeeAlso: INT 86"NetBIOS"

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