Pathmaker Programming Guide

Specifying CALL and SEND Parameters
Creating Requesters
5–34 067868 Tandem Computers Incorporated
CALL Parameters You use the CALL parameters screen to specify the mapping between reference objects
from this requester and reference objects in one of the requesters it is calling.
The Pathmaker product supplies most of the information on this screen by matching
the formal parameter list (Requester Parameters screen) of the called requester to
reference objects in the requester context of this requester. The Pathmaker product will
only match reference objects if they have the same name, the same length, and are of
compatible data types. If a parameter on the Requester Parameters screen of the called
requester does not exactly match a reference object in the requester context of the
calling requester, that parameter will not appear on the CALL Parameters screen. If
you are using parameters that do not have the same name, you will have to complete
some portions of the CALL Parameter screen yourself.
Here are guidelines for using the CALL Parameters screen:
Each reference object listed on the Requester Parameters screen of the called
requester must match a reference object on the CALL Parameters screen.
Matching fields do not have to have the same name, but they must be the same
length and must be compatible data types.
You must complete the Requester Parameters screen for the called requester before
you can complete the CALL Parameter Definition screen for the calling requester.
If you make any changes to the Requester Parameters screen for a called requester,
you must also change the CALL Parameter Definition screen for the calling
requester. Both requesters must then be regenerated and recompiled.
All CALL parameters are called by reference; if a value is changed in the called
program, it is also changed in the calling requester.
You can choose to pass the value either as it existed before input from the
keyboard (before-image) or after input (after-image) from the keyboard. The
before-image is the value saved after the previous CALL or SEND, or if there is no
previous CALL or SEND, the initial values of the field. The after-image is the data
the end user entered.
By default, the Pathmaker product sends the after-image—that is, the data that the
end user typed in—to the called requester. You can send the before-image to the
called requester by using the Before/After column of the CALL Parameter
Definition screen.
The Pathmaker product generates CALL...USING statements in the Procedure
Division of the SCREEN COBOL requester code from the information you specify
on the CALL Parameter Definition screen.
Figure 5-8 illustrates how the Pathmaker product maps CALL parameters and
requester parameters. In the figure, notice that the Pathmaker product does not match
K-DEF and C-DEF on the CALL Parameter Definition screen because they do not have
the same name. You would have to type in K-DEF to match it to C-DEF.