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curs_outopts(3)                 Library calls                curs_outopts(3)


       clearok, idlok, idcok, immedok, leaveok, setscrreg, wsetscrreg,
       scrollok - set curses output options


       #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 scrollok(WINDOW *win, bool bf);

       int setscrreg(int top, int bot);
       int wsetscrreg(WINDOW *win, int top, int bot);


       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(3X).

       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 is not 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 TRUE as second argument, any change in the
       window image, such as the ones caused by waddch, wclrtobot, wscrl,
       etc., automatically causes a call to wrefresh.  However, it may degrade
       performance considerably, due to repeated calls to wrefresh.  Calling
       immedok with FALSE as second argument restores the default behavior,
       i.e., deferring screen updates until a refresh is needed.

       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.

       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 to get the physical scrolling effect on
       the terminal, it is also necessary to call idlok).

   setscrreg, wsetscrreg
       The setscrreg and wsetscrreg routines allow the application programmer
       to set a software scrolling region in a window.  The top and bot
       parameters 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


       The functions setscrreg and wsetscrreg return OK upon success and ERR
       upon failure.  All other routines that return an integer always return

       X/Open Curses does not specify any error conditions.

       In this implementation,

       o   those functions that have a window pointer will return an error if
           the window pointer is null

       o   wsetscrreg returns an error if the scrolling region limits extend
           outside the window boundaries.


       Note that clearok, leaveok, scrollok, idcok, and setscrreg may be

       The immedok routine is useful for windows that are used as terminal


       These functions are described in X/Open Curses, Issue 4.

       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.  X/Open Curses does not require this, and ncurses
       avoids doing it to perform better vertical-motion optimization at
       wrefresh time.

       X/Open Curses does not mention that the cursor should be made invisible
       as a side-effect of leaveok.  SVr4 curses documentation does this, but
       the code does not.  Use curs_set to make the cursor invisible.


       ncurses formerly treated nl(3X) and nonl(3X) as both input and output
       options, but no longer; see curs_inopts(3X).


       curses(3X), curs_addch(3X), curs_clear(3X), curs_initscr(3X),
       curs_refresh(3X), curs_scroll(3X), curs_variables(3X)

ncurses 6.5                       2024-04-20                  curs_outopts(3)

ncurses 6.5 - Generated Sat May 4 10:25:39 CDT 2024
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