NetIPC 3000/XL Programmer's Reference Manual (5958-8600)

Chapter 1 29
NetIPC Fundamentals
Using NetIPC for Interprocess Communication
Figure 1-9 Using IPCDEST
Sending and Receiving Data Over a Connection
Once a virtual circuit connection is established, the two processes can
exchange data using the NetIPC calls IPCSEND and IPCRECV. Either
process can send or receive data. IPCSEND is used to send data on an
established connection; it is analogous to “speaking” over a telephone
connection. IPCRECV is used to receive data on an established
connection; the use of IPCRECV is similar to “listening” at our telephone
handset. (Note that IPCRECV has a dual function: to complete a virtual
circuit connection as well as to receive data on a previously established
connection.)
X.25 Access
Direct access to level 3 (X.25) provides message mode transfer. Stream
mode is not supported for X.25. Each IPCRECV returns a complete
message (provided the data length specified is of sufficient size). The
X.25 protocol signals the end of message and NetIPC buffers the
message until an IPCRECV (or required IPCRECVs), retrieve it.
PROCESS A
PROCESS B
IPCCREATE
IPCRECV
IPCCREATE
IPCRECVCN
1) Create call socket
2) Create destination descriptor
3) Request connection
4) Check status of connection
1) Create call socket
2) Receive connection request
IPCDEST
IPCCONNECT