NET/MASTER Network Control Language (NCL) Programmer's Guide

Obtaining Input From a Panel
Working With Panels
106160 Tandem Computers Incorporated 14–71
In the case of asynchronous panels, if the FMTINPUT operand is not specified in the
panel description file, the input fields will only be reset the first time the panel is
displayed or when the panel is redisplayed after the operator has signalled the end of
input (by pressing ENTER or a defined function key). This means that input can be
entered continuously by the operator while the panel output fields are being rewritten
as output is directed to the terminal. If the FMTINPUT operand is specified in the
panel description file, input field initialization will be processed as defined by the
operands of the #OPT statement.
Controlling Input Field
Formats
When a panel is displayed, a data stream is created to format the physical screen as
defined in the panel description file: for example, a panel may be displayed
repeatedly, the display time being controlled by the INWAIT operand. Here, the
INWAIT timer can expire while data or a command is still being entered in the panel.
The entered data is ignored and the input field cleared on the redisplayed panel. If
input fields are formatted, any data currently entered in a field from a previous
display of the panel is erased and the cursor position changes.
The #OPT FMTINPUT statement lets you avoid this problem by letting the NCL
process determine when the input fields are formatted. So, if you are entering data
when the screen is refreshed and you specify FMTINPUT=NO, then the data you enter
remains and you can complete entering the data unaffected.
By varying the FMTINPUT operand setting (through a variable set from within the
NCL process) between YES and NO, the NCL process can toggle input field formatting
on and off.
The first time a panel is displayed, it should always specify FMTINPUT=YES to ensure
that the physical screen is correctly formatted. When the panel is subsequently
redisplayed (usually after the INWAIT timer expires), you can specify
FMTINPUT=NO.
Controlling Output Field
Attributes
It is possible to change the attributes of an input field to those of an outvar field by
using the ASSIGN verb with the OPT=SETOUT operand. The target variables of the
ASSIGN verb adopt the attributes of an OUTVAR field. If the field being changed has
standard input field attributes, standard output field attributes are adopted by the
output field.
The standard system-wide field attributes for different types of fields, including input
and output fields, are defined by SYSPARMS commands. For more information on
standard system-wide attributes, see the subsection “System-Wide Panel Field
Attributes,” earlier in this section.
You can change the attributes of the target variables back to their original values by
using the ASSIGN verb with the RESETOUT operand.