INT 21 - LANtastic - SEND UNSOLICITED MESSAGE                                   
	AX = 5F98h
	DS:SI -> message buffer (see #01730)
Return: CF clear if successful
	CF set on error
	    AX = error code
Note:	v4.1- return no errors
SeeAlso: AX=5F99h


Format of LANtastic message buffer:
Offset	Size	Description	(Table 01730)
 00h	BYTE	reserved
 01h	BYTE	message type
		00h general
		01h server warning
		02h-7Fh reserved
		80h-FFh user-defined
 02h 16 BYTEs	ASCIZA NUL-terminated ASCII string.	The ASCIZ string "ABC" consists of the four bytes 41h, 42h, 43h, and 00h.  Unless otherwise specified, maximum lengths given in the interrupt list do not include the terminating NUL. destination machine name
 12h 16 BYTEs	ASCIZA NUL-terminated ASCII string.	The ASCIZ string "ABC" consists of the four bytes 41h, 42h, 43h, and 00h.  Unless otherwise specified, maximum lengths given in the interrupt list do not include the terminating NUL. server name which user must be logged into
 22h 16 BYTEs	ASCIZA NUL-terminated ASCII string.	The ASCIZ string "ABC" consists of the four bytes 41h, 42h, 43h, and 00h.  Unless otherwise specified, maximum lengths given in the interrupt list do not include the terminating NUL. user name
 32h 16 BYTEs	ASCIZA NUL-terminated ASCII string.	The ASCIZ string "ABC" consists of the four bytes 41h, 42h, 43h, and 00h.  Unless otherwise specified, maximum lengths given in the interrupt list do not include the terminating NUL. originating machine name (filled in when received)
 42h 80 BYTEs	message text