RSC/MP 7.2 Programming Manual

Unsolicited Message Service
HP NonStop Remote Server Call (RSC/MP) Programming Manual—522360-004
8-2
Design Guidelines
RSC/MP functions on the workstation allow the application to receive and reply to
unsolicited messages. The workstation application periodically calls (or requests
asynchronous notification of a UMS) the RscUmsCheck function to determine whether
a UMS message has arrived and to retrieve the message. The RscUmsReply function
returns a reply to the TDP, which returns it to the Guardian process.
Design Guidelines
When designing applications that use unsolicited messages, follow these guidelines:
•
In the host application server, fill in the UMS header to identify the workstation that
should receive messages. The UMS header must precede all unsolicited
messages.
•
Determine if you want a reply returned. If so, use the Guardian WRITEREAD
procedure to send the message to the TDP.
•
In the RSC/MP client application, use the RscUmsCheck function to determine
when a UMS message has arrived. To prevent the need for an RscUmsCheck,
consider using a form of asynchronous UMS receipt notification available for your
platform (RscNotifySem available on Windows and UNIX; RscNotifyWin and
RscNotifyThread available on Windows only).
Figure 8-1. Unsolicited Message Service, Flow of Information
$TDP.#RSCUMS
RscUmsReply
Function
RscUmsCheck
Function
User-Written
Program
Client Application NonStop System
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2
3
4
Legend
WRITEREAD Procedure
WRITE Procedure
CDT009
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and
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