Sequence Packet Exchange (SPX)
SPX is a connection-based, reliable,
sequenced transport protocol which provides:
 guaranteed packet delivery
- 
ensuring that packets are received in order by the
destination endpoint
 flow control
- 
regulating the speed at which packets are
sent and received by both the sending and receiving processes
The TLI (Transport Layer Interface) library
provides routines with which to access SPX.
SPX supports the following calls
from the TLI library:
 t_accept
- 
accept a
connect request
 t_alloc
- 
allocate a
library structure
 t_bind
- 
bind an address to
a transport endpoint
 t_close
- 
close a
transport endpoint
 t_connect
- 
establish a connection with
another transport user
 t_error
- 
produce an
error message
 t_free
- 
free a library
structure
 t_getinfo
- 
get protocol-specific
service information
 t_getstate
- 
get the
current state
 t_listen
- 
listen for a
connect request
 t_look
- 
look at the current event
on a transport endpoint
 t_open
- 
establish a transport endpoint
 t_optmgmt
- 
manage options for
a transport endpoint
 t_rcv
- 
receive data or expedited data sent over a connection
 t_rcvdis
- 
retrieve information
from disconnect
 t_snd
- 
send data or expedited
data over a connection
 t_snddis
- 
send user-initiated
disconnect request
 t_sync
- 
synchronize
transport library
 t_unbind
- 
disable a
transport endpoint
``Using the SPX protocol''
describes how to use these routines to access SPX.
The structures used by the TLI
interface to SPX are:
- 
t_bind
 
- 
t_call
 
- 
t_discon
 
- 
t_info
 
- 
t_optmgmt
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Service Advertising Protocol (SAP)
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Internet Packet Exchange (IPX)
© 2003 Caldera International, Inc.  All rights reserved.
SCO OpenServer Release 5.0.7 -- 11 February 2003