RSC/MP Programming Manual

Message Handling Recovering From Data Communications Failures
Table 7-1. Subsystem Error Codes
Error Code
Base Value
Error Type Description
RSC_API_BASE
0x0000
API errors. See the Remote Server Call
(RSC/MP) Messages Manual
RSC_PATHSEND_BASE
0x2000
Pathsend interface errors. See the Pathway
Application Programming Guide and the
Remote Server Call (RSC/MP) Messages
Manual.
RSC_FILE_SYSTEM_BASE
0x3000
HP NonStop or Guardian system errors.
See the Guardian Procedure Errors and
Messages Manual.
RSC_UMS_BASE
0x6000
Unsolicited Message Service (UMS) errors.
See the Remote Server Call (RSC/MP)
Messages Manual.
RSC_PIPE_BASE
0xA000
Piccolo errors. See the Remote Server Call
(RSC/MP) Messages Manual.
This is an example of an error message returned from another subsystem:
The Piccolo Communications Subsystem has reported retryable
connection error 4-0 ( A004-0000 Hex ). Cannot find name
called or no answer. The destination process or node you are
trying to contact does not exist.
In this message, the error number is 4, and the subsystem is Piccolo (hexadecimal
base va lue of A000).
Recovering From Data Communications
Failures
When a communications connection failure occurs after an application has connected
to the host using the RscConnect function call, an appropriate error is returned from
the next RSC/MP API function that attempts to communicate with the host; for
example, the RscWriteRead function. Whe n an error is returned, the application should
call the RscErrorInfo function and examine its result code to determine the type of
error. For all communications connection failures, the subsystem is
RSC_PIPE_SUBSYS TEM.
Use these methods to recover from RSC/MP application data communications failures:
Discard the current RSC/MP connection and attempt to re-establish it. The
application can then create a new connection and session using the RscConnect
and RscBeginSession function calls.
Configure multiple TDPs or Pipeman processes on the host system to provide
alternate destinations in case of failures of components between the workstation
HP NonStop Remote Server Call (RSC/MP) Programming Manual — 522360-006
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