HP 9000 Series 300 Tutorials Manual page 201

the array by addch or its equivalent. If text highlighting is to be changed for
a given character or set of characters, an update to the current attribute set
must be performed by attrset (or its equivalent) before addch is performed.
The beginning default attribute set disables all highlighting.
16-bit Data Handling
curses uses an NLS environment when displaying 16-bit characters. This
means curses uses the HP-15 code scheme for interfacing (Input/Output), and
users must set up their own NLS environment. Also, curses treats a 16-bit
character code as an upper 8-bit code and a lower 8-bit code. In short, curses
can pass only 8-bit characters at one time.
curses displays and handles 16-bit characters as follows:
• Overwrite on a 16-bit character.
If the write of a character starts from either the right half or the left
half of a 16-bit character, the remaining half is changed to a space
character.
• Insert character on a 16-bit character.
If the insert of a character starts from the right half of a 16-bit
character, the left half and the right half are changed to a space
character.
• Write a 16-bit character on the right boundary.
When a 16-bit character is added to the right margin, a space character
is added to the right margin and a 16-bit character is added to the left
margin of the next line.
• Delete a 16-bit character.
If the cursor is at either the right half or left half of a 16-bit character,
the remaining half is changed to a space character.
• Clear a 16-bit character.
If the cursor is at the right half of a 16-bit character, the left half is
changed to a space character.
• Move a cursor on a 16-bit character.
When the specified row
(y) and column (x) is on the right half of a
16-bit character, the cursor position (the left half or the right half of
a 16-bit character) depends on the terminal's facility. But when the
Using Curses and Terminfo 1-3