HP-UX TN3270 Users Guide, March 1998

84 Chapter 3
Getting Started with 3270 Emulation
Double-Byte Characters
Double-Byte Character in Column 80
When a field in the 3270 screen occupies more than one line, a
double-byte character can sometimes be split at the end of a line, that is,
the first byte of the character occupies position 80 of one line, and the
second byte occupies position 1 of the next line.
The TN3270 emulation program and the host will recognize the
double-byte character and process it correctly. However, the
character-based TN3270 emulation program cannot display it correctly
on the screen. Instead, it displays a “split character” marker in these two
positions.
The default character displayed is - (hyphen). You can change this to a
different ASCII character if required. You may want to choose a
character that is not normally used for any other purpose in the host
application to make it easier to recognize these split characters. To do
this, set the environment variable SNAP3270_SPLIT_CHAR to the
hexadecimal value representing the ASCII character you want to use.
For example, setting SNAP3270_SPLIT_CHAR to 40 displays the
character @ (0x40) in both positions of the split character.
On some terminal types, writing a character to position 80 on the last
line of the display causes a line feed. To avoid this problem, the TN3270
emulation program does not normally display a double-byte character
that occupies positions 79 and 80 on the last line of the display. If your
terminal can handle this correctly, you can set the environment variable
SNAP3270_LOWER_RIGHT to override this. The program attempts to
display a double-byte character in these positions if
SNAP3270_LOWER_RIGHT is set to any non-null value, and the program
does not attempt to display it if SNAP3270_LOWER_RIGHT is not set or is
set to a null string.
Motif The Motif TN3270 emulation program includes an additional column in
the screen display (column 81) when you are using a double-byte host
language. This column is normally left blank, with the data displayed
only in the first 80 columns.
If a double-byte character occurs at the end of a line, it is displayed in
positions 80 and 81, and position 1 of the following line (where the
second byte of the character would normally be displayed) is left blank.
The TN3270 emulation program and the host recognize the double-byte