curs_outopts(3CURSES) Curses Library Functions curs_outopts(3CURSES)NAME
curs_outopts, clearok, idlok, idcok, immedok, leaveok, setscrreg,
wsetscrreg, scrollok, nl, nonl - curses terminal output option control
routines
SYNOPSIS
cc [ flag ... ] file ... -lcurses [ library ... ]
#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);
DESCRIPTION
These routines set options that deal with output within curses. All
options are initially FALSE, unless otherwise stated. It is not neces‐
sary to turn these options off before calling endwin().
With the clearok() routine, if enabled (bf is TRUE), 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.
With the idlok() routine, if enabled (bf is TRUE), curses considers
using the hardware insert/delete line feature of terminals so equipped.
If disabled (bf is FALSE) , curses very seldom uses this feature. (The
insert/delete character feature is always considered.) 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 applica‐
tions where it isn't really needed. If insert/delete line cannot be
used, curses redraws the changed portions of all lines.
With the idcok() routine, if enabled (bf is TRUE), curses considers
using the hardware insert/delete character feature of terminals so
equipped. This is enabled by default.
With the immedok() routine, if enabled (bf is 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 the performance considerably, due to repeated calls to wre‐
fresh(). 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 hap‐
pens 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 pro‐
grammer 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 up one 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 char‐
acter of the last line. If disabled, (bf is FALSE), the cursor is left
on the bottom line. If enabled, (bf is TRUE), wrefresh() is called on
the window, and the physical terminal and window are 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 newline is translated into
carriage return and linefeed on output, and whether return is trans‐
lated into newline on input. Initially, the translations do occur. By
disabling these translations using nonl(), curses is able to make bet‐
ter use of the linefeed capability, resulting in faster cursor motion.
RETURN VALUESsetscrreg() and wsetscrreg() return OK upon success and ERR upon fail‐
ure. All other routines that return an integer always return OK.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│MT-Level │Unsafe │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOcurs_addch(3CURSES), curs_clear(3CURSES), curs_initscr(3CURSES),
curs_refresh(3CURSES), curs_scroll(3CURSES), curses(3CURSES),
attributes(5)NOTES
The header <curses.h> automatically includes the headers <stdio.h> and
<unctrl.h>.
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.
SunOS 5.10 31 Dec 1996 curs_outopts(3CURSES)
