Int 21 Fn 5FC8  - Lantastic V4.0+ - Schedule Server Shutdown               [N]

   AX = 5FC8h
   ES:DI -> ASCIZ server name in form "\\machine"
   DS:SI -> ASCIZ reason string (80 characters)
   CX = number of minutes until shutdown (0 = immediate)
   DX = option flags (see #1433)

Return: CF clear if successful
   CF set on error
       AX = error code

See Also: AX=5FC9h

Bitfields for LANtastic option flags:
Bit(s) Description (Table 1433)
 0 auto reboot
 1 do not notify users
 2 halt after shutdown
 3 shutdown due to power fail (used by UPS)
 4-7   reserved
 8-14  user definable
 15    reserved