#include <curses.h>
int clearok(WINDOW *win, bool bf);
int idlok(WINDOW *win, bool bf);
void idcok(WINDOW *win, bool bf);
void immedok(WINDOW *win, bool bf);
int leaveok(WINDOW *win, bool bf);
int setscrreg(int top, int bot);
int wsetscrreg(WINDOW *win, int top, int bot);
int scrollok(WINDOW *win, bool bf);
int nl(void);
int nonl(void);
These routines set options that change the style of output
within curses. All options are initially
FALSE, unless
otherwise stated. It is not necessary to turn these
options off before calling endwin().
If clearok() is called with TRUE as
argument, the next call
to wrefresh() with this window will clear the screen
completely and redraw the entire screen from scratch. This
is useful when the contents of the screen are uncertain,
or in some cases for a more pleasing visual effect. If
the win argument to clearok() is the
global variable curscr,
the next call to wrefresh() with any window causes the
screen to be cleared and repainted from scratch.
If idlok() is called with TRUE as second
argument, curses
considers using the hardware insert/delete line feature of
terminals so equipped. Calling idlok() with
FALSE as second
argument disables use of line insertion and deletion.
This option should be enabled only if the application
needs insert/delete line, for example, for a screen editor. It is disabled
by default because insert/delete line
tends to be visually annoying when used in applications
where it isn't really needed. If insert/delete line cannot be used,
curses redraws the changed portions of all lines.
If idcok() is called with FALSE as second
argument, curses
no longer considers using the hardware insert/delete character feature of
terminals so equipped. Use of character
insert/delete is enabled by default. Calling idcok() with
TRUE as second argument re-enables use of character insertion
and deletion.
If immedok() is called with an argument of
TRUE, any change in the window image, such as the ones caused
by waddch(), wclrtobot(),
wscrl(), etc., automatically cause a call to
wrefresh(). However, it may degrade performance
considerably, due to repeated calls to wrefresh().
It is disabled by default.
Normally, the hardware cursor is left at the location of
the window cursor being refreshed. The leaveok() option
allows the cursor to be left wherever the update happens
to leave it. It is useful for applications where the cursor is not used,
since it reduces the need for cursor motions.
If possible, the cursor is made invisible when this option is enabled.
The setscrreg() and wsetscrreg()
routines allow the application programmer to set a software scrolling region
in a window. top and bot are the line numbers of
the top and bottom margin of the scrolling region. (Line 0 is the top
line of the window.) If this option and scrollok() are
enabled, an attempt to move off the bottom margin line
causes all lines in the scrolling region to scroll one
line in the direction of the first line. Only the text of
the window is scrolled. (Note that this has nothing to do
with the use of a physical scrolling region capability in
the terminal, like that in the VT100. If idlok() is
enabled and the terminal has either a scrolling region or
insert/delete line capability, they will probably be used
by the output routines.)
The scrollok() option controls what happens when the
cursor of a window is moved off the edge of the window or
scrolling region, either as a result of a newline action
on the bottom line, or typing the last character of the
last line. If disabled, (bf is FALSE), the
cursor is left on the bottom line. If enabled, (bf
is TRUE), the window is scrolled up one line (Note that in
order to get the physical scrolling effect on the terminal, it is also
necessary to call idlok()).
The nl() and nonl() routines control
whether the underlying display device translates the return key into newline on
input, and whether it translates newline into return and
line-feed on output (in either case, the call addch('0)
does the equivalent of return and line feed on the virtual
screen). Initially, these translations do occur. If you
disable them using nonl(), curses
will be able to make better use of the line-feed capability, resulting in
faster cursor motion. Also, curses will then be able to detect the return key.
The functions setscrreg() and
wsetscrreg() return OK upon success and
ERR upon failure. All other routines that return
an integer always return OK.
These functions are described in the XSI Curses standard,
Issue 4.
The XSI Curses standard is ambiguous on the question of
whether raw()() should disable the
CRLF translations controlled by nl()
and nonl(). BSD curses did turn off these
translations; AT&T curses (at least as late as SVr1) did
not. We choose to do so, on the theory that a programmer
requesting raw input wants a clean (ideally 8-bit clean)
connection that the operating system does not mess with.
Some historic curses implementations had, as an undocumented feature, the
ability to do the equivalent of
clearok(..., 1) by saying
touchwin(stdscr) or clear(stdscr).
This will not work under ncurses.
Earlier System V curses implementations specified that
with scrollok() enabled, any window modification
triggering a scroll also forced a physical refresh. XSI Curses does
not require this, and ncurses avoids doing it in order to perform better
vertical-motion optimization at wrefresh() time.
Note that clearok(), leaveok(),
scrollok(), idcok(),
nl(), nonl(), and
setscrreg() may be macros.
The immedok() routine is useful for windows that are used
as terminal emulators.
PTC MKS Toolkit for Professional Developers
PTC MKS Toolkit for Enterprise Developers
PTC MKS Toolkit for Enterprise Developers 64-Bit Edition
- Functions:
- curs_addch(), curs_clear(), curs_initscr(), curs_refresh(), curs_scroll(), curses()
PTC MKS Toolkit 10.5 Documentation Build 40.