Pathway/iTS TCP and Terminal Programming Guide

Processing Double-Byte Character Sets
Compaq NonStop™ Pathway/iTS TCP and Terminal Programming Guide—426751-001
8-10
Data Division
Screen Section Considerations
When you develop Pathway applications for double-byte character sets, you must
consider the following when you write the Screen Section of the Data Division of your
SCREEN COBOL program unit.
Permissible Character-String Symbols
In the Screen Section the character-string symbol N can be mixed with only the X, A, 9,
0, and B character-string symbols. Some examples are:
SCREEN SECTION.
:
03 SS-KANJI-ONLY PIC N at ...
:
03 SS-KANJI-CONTIG PIC N....N at ...
* (maximum of 30 Ns)
:
03 SS-KANJI-IMPLIED PIC N(n) at ...
* (where n is 1 to 256)
:
03 SS-KANJI-MIXED-ALPHA PIC NXN at ...
:
05 SS-KANJI-MIXED PIC NXNXAAXN at ...
* (mixed)
:
03 SS-KANJI-MIXED-EDITED PIC NXN0NBXN at ...
* (mixed edited)
:
03 SS-PICX-DATA PIC X(70) at ...
* (Any data can be entered here.
* It can consist of a
* combination of single and
* double-byte data.)
Screen Field Limits
You need to be aware of special limitations when you design applications for IBM 3270
devices that declare screen fields containing double-byte or mixed (single-byte
alphanumeric and double-byte) data and for Fujitsu terminals that include screen fields
that wrap from one line to the next. Of course, no screen-field data item can be greater
than 256 bytes. When one is too long, it is truncated, regardless of the device.
In creating screen fields for mixed items for IBM and Fujitsu equipment, the translation
library inserts shift-out/shift-in characters into the data stream to bracket double-byte
character substrings. On IBM equipment the shift characters occupy display space. On
Fujitsu equipment the shift characters do not take display space and, therefore, do not
affect the data displayed. Because the JET 6530 terminal and the 6530 terminal
emulator use double-byte characters in Shift-JIS format, it is not necessary to insert shift
characters into the data stream to be transmitted when using those terminals.