TS/MP Pathsend and Server Programming Manual (H06.05+, J06.03+)

Designing Requester Programs
To facilitate the accessing of Pathway server classes from different transaction sources, you can
develop requester programs for a Pathway application that use any of these access approaches:
• SCREEN COBOL and the TCP
• SCREEN COBOL and the TCP with the intelligent device support (IDS) facility
• The Pathsend procedure calls
• The RSC/MP product, with or without the POET
• The GDSX product
In Table 3 (page 36), key technical and business considerations are mapped to each way of
accessing Pathway servers. More information about each approach is provided after the table.
Table 3 Considerations for Requester Programs
Support for
Context
Sensitivity
TMF
Support
Fault
Tolerance
Ease of
Development
High
Performance
Multi-
Threading
Capability
Support for
Intelligent
Devices
Large
Number of
I/O Devices
Server
Access
Approach
XXXXXTCP
XXXXXXTCP with
IDS
XXXXPathsend
XXXXXXRSC/MP or
POET
XXXXXXGDSX
SCREEN COBOL Requesters
Screen programs for Pathway terminals perform a variety of front-end functions for your Pathway
application and are typically written as single-threaded programs in the SCREEN COBOL language.
This language offers a simple programming environment and screen-management system to drive
NonStop terminals and IBM 3270 terminals. SCREEN COBOL supports both conversational mode
(for either block-mode or conversational-mode terminals) and intelligent mode (for intelligent devices
and communications lines).
When you write a screen program in SCREEN COBOL, you can take advantage of the features
of the Pathway/iTS TCP. As supplied by HP, the TCP supports:
• Fault tolerance
• TMF transactions
• Multitasking of single-threaded screen programs
• Access to server processes with Pathway server classes
• Unsolicited-message processing (UMP)
• System management interfaces (that is, PATHCOM or the Pathway management programming
interface)
SCREEN COBOL requester programs do not perform any file I/O operations except to terminals
and server classes. A file I/O operation to a server class, which is in the form of a request message,
is initiated by the requester program by using the SCREEN COBOL SEND statement.
For information about designing and coding SCREEN COBOL requesters, refer to the Pathway/iTS
TCP and Terminal Programming Guide.
36 Designing Your Application