Pathway/iTS SCREEN COBOL Reference Manual (H06.10+, J06.03+)

Procedure Division
HP NonStop Pathway/iTS SCREEN COBOL Reference Manual—426750-003
6-60
DISPLAY BASE Statement
DISPLAY BASE Statement
The DISPLAY BASE statement formats the specified screen from the screen definition
in the Screen Section. The statement selects the screen description for subsequent
operations but does not display the screen.
The DISPLAY BASE DYNAMIC statement performs the same function as the two-
statement sequence DISPLAY BASE and DISPLAY. (DISPLAY follows DISPLAY
BASE.)
The DISPLAY BASE statement operates differently for terminals in block mode from
terminals in conversational mode. It cannot be used for communication with intelligent
devices.
For terminals in block mode, DISPLAY BASE formats data for screen literals, VALUE
clauses, null characters, and fill characters, and establishes attributes for screen fields.
DISPLAY BASE also clears the current screen display. DISPLAY BASE does not
cause current values from Working-Storage items to appear in output fields of the
screen; DISPLAY formats these values.
For terminals in both block and conversational mode, DISPLAY BASE establishes the
current screen, which serves as the foundation for all other screen operations.
Therefore, this statement must run before other display operations run. A second
DISPLAY BASE can run at any time to establish a new screen, or to reestablish the
same screen.
DYNAMIC
specifies that nonliteral screen fields can acquire their initial contents from their
FROM or USING Working-Storage data item. A subsequent DISPLAY statement is
not needed to display the initial Working-Storage values.
In addition, the DYNAMIC modifier provides the capability of changing the screen
field attribute settings at run-time by using the contents of individual attribute
elements in an associated control structure.
base-screen-name
is the name of the base screen.
When a shadowed screen field has an associated Working-Storage item with its
SELECT bit set to 1, the screen field acquires its initial screen contents from its FROM
or USING Working-Storage data item. Otherwise, the initial screen contents are
acquired from the compile-time literal value or the default initial value.
DISPLAY BASE (without the DYNAMIC modifier) does not physically display the
screen. The screen data is displayed when one of these events occurs:
•
Terminal buffer (TERMBUF) fills up
DISPLAY BASE [DYNAMIC] base-screen-name