curs_outopts(3X)curs_outopts(3X)NAME
curs_outopts: clearok, idlok, idcok immedok, leaveok, setscrreg,
wsetscrreg, scrollok, nl, nonl - curses terminal output option control
routines
SYNOPSIS
#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
necessary 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
applications 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.
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curs_outopts(3X)curs_outopts(3X)
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 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 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 character 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 translated
into newline on input. Initially, the translations do occur. By
disabling these translations using nonl, curses is able to make better
use of the linefeed capability, resulting in faster cursor motion.
RETURN VALUE
setscrreg and wsetscrreg return OK upon success and ERR upon failure.
All other routines that return an integer always return OK.
NOTES
The header file <curses.h> automatically includes the header files
<stdio.h> and <unctrl.h>.
Note that clearok, leaveok, scrollok, idcok, nl, nonl and setscrreg may
be macros.
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curs_outopts(3X)curs_outopts(3X)
The immedok routine is useful for windows that are used as terminal
emulators.
SEE ALSOcurses(3X), curs_addch(3X), curs_clear(3X), curs_initscr(3X),
curs_scroll(3X), curs_refresh(3X)
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