Int 7A  - Novell Netware - Spx Driver - Establish Spx Connection           [N]

   BX = 0011h
   AL = retry count
   AH = watchdog flag
   ES:SI -> Event Control Block (see #3481 at BX=0003h)

Return: AL = status (00h,EFh,FDh,FFh) (see #3496)
   DX = assigned connection ID number
Desc:  attempt to establish a connection with a listening socket

Notes: there should always be at least two SPX ECB's listening to a socket, so
     that NetWare can perform its internal packet exchanges
   the first fragment should start with a SPX header (see #3497).  Fill
     in all destination addresses.
   this function is supported by Advanced NetWare 2.1+

See Also: BX=0000h,BX=0012h,BX=0013h,BX=0014h,BX=0015h

(Table 3496)
Values for SPX function status:
 00h   attempting to contact destination socket
 EEh   no such connection
 EFh   local connection table full
 FDh   buffer size not 42 or fragment count not 1
 FFh   sending socket not open

Format of SPX header:
Offset Size    Description (Table 3497)
 00h   WORD    (big-endian) checksum
 02h   WORD    (big-endian) length in bytes of total packet
 04h   BYTE    transport control
 05h   BYTE    packet type (see #3487 at INT 7A/BX=0003h)
 06h 10 BYTEs  destination internet address
 10h   WORD    (big-endian) destination socket
 12h 10 BYTEs  source internet address
 1Ch   WORD    (big-endian) source socket
 1Eh   BYTE    connection control (see #3498)
 1Fh   BYTE    datastream type
       FEh terminate connection request packet
       FFh terminate connection acknowledgement packet
       other user-defined, ignored by SPX
 20h   WORD    (big-endian) source connection ID
 22h   WORD    (big-endian) destination connection ID
 24h   WORD    (big-endian) sequence number
 26h   WORD    (big-endian) acknowledge number
 28h   WORD    (big-endian) allocation number

See Also: #3486

Bitfields for SPX connection control:
Bit(s) Description (Table 3498)
 3-0   unused???
 4 end of message
 5 reserved
 6 acknowledgement required
 7 system packet