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

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D Migration From PTOP to NetIPC
and RPM
The PTOP (Program-to-Program communication) service is available on
DS/3000 and NS 3000/V. It is a master-slave protocol wherein a master
process creates a slave process on a remote node, the master sends
data-exchange requests to the slave, and the slave accepts or rejects the
master requests.
The NetIPC (Network InterProcess Communication) and RPM (Remote
Process Management) services are available on NS 3000/V and
NS 3000/XL. These services provide a more flexible alternative to PTOP
for developing distributed applications. Since PTOP is not supported on
NS 3000/XL, any PTOP application to be migrated to an MPE XL
system must be rewritten to use NetIPC and RPM. These guidelines
provide steps for the conversion.
A distributed application using PTOP or NetIPC/RPM can be divided
into three phases:
• Creation of the remote (slave) process and the establishment of a
communications channel between the local (master) and the remote
(slave) processes.
• Data exchange over the communications channel.
• Process termination and the shut down of the communications
channel.
The rest of this appendix is divided according to creating processes,
exchanging data, and terminating processes. The sections are then
subdivided according to what you have to do on a master program and
on a slave program.