Format of NetBIOS Network Control Block:
Offset	Size	Description	)
 00h	BYTE	command code (see #03250)
 01h	BYTE	return code (see #03248)
 02h	BYTE	local session number (LSN)
 03h	BYTE	"ncb_num" datagram table entry from ADD NAME
 04h	DWORD	-> I/O buffer
 08h	WORD	length of data in buffer
 0Ah 16 BYTEs	remote system to call
 1Ah 16 BYTEs	network name of local machine
 2Ah	BYTE	receive timeout in 1/2 seconds
 2Bh	BYTE	send timeout in 1/2 seconds
 2Ch	DWORD	-> FAR post handler	/* int (far *ncb_post)(); */
 30h	BYTE	network adapter number on which to execute command
		00h-03h IBM NetBIOS specs
		F0h-FFh Eicon NABios interface (see also INT 7B"Eicon")
 31h	BYTE	command completion code (see #03248)
 32h 14 BYTEs	reserved for network card