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curs_outopts(3X)								 curs_outopts(3X)

       clearok,  idlok,  idcok,  immedok,  leaveok,  setscrreg,  wsetscrreg, scrollok, nl, nonl -
       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 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 use-
       ful 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

       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 dis-
       abled  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 TRUE as argument, 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.

       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 mar-
       gin 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 bot-
       tom 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  nec-
       essary 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('\n') 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

       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 transla-
       tions; 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 to perform better  vertical-motion  optimization
       at wrefresh time.

       The  XSI  Curses  standard  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.

       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.

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

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