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curs_clear(3X)							curs_clear(3X)

NAME
       erase, werase, clear, wclear, clrtobot, wclrtobot, clrtoeol, wclrtoeol
       - clear all or part of a	curses window

SYNOPSIS
       # include <curses.h>

       int erase(void);
       int werase(WINDOW *win);
       int clear(void);
       int wclear(WINDOW *win);
       int clrtobot(void);
       int wclrtobot(WINDOW *win);
       int clrtoeol(void);
       int wclrtoeol(WINDOW *win);

DESCRIPTION
       The erase and werase routines copy blanks to every position in the win-
       dow, clearing the screen.

       The  clear and wclear routines are like erase and werase, but they also
       call clearok, so	that the screen	is cleared completely on the next call
       to wrefresh for that window and repainted from scratch.

       The clrtobot and	wclrtobot routines erase from the cursor to the	end of
       screen.	That is, they erase all	lines below the	cursor in the  window.
       Also,  the  current  line  to  the  right  of the cursor, inclusive, is
       erased.

       The clrtoeol and	wclrtoeol routines erase the current line to the right
       of the cursor, inclusive, to the	end of the current line.

       Blanks created by erasure have the current background rendition (as set
       by wbkgdset) merged into	them.

RETURN VALUE
       All routines return the integer OK on success and ERR on	failure.   The
       SVr4.0  manual  says "or	a non-negative integer if immedok is set", but
       this appears to be an error.

       X/Open defines no error conditions.  In this implementation,  functions
       using a window pointer parameter	return an error	if it is null.

NOTES
       Note  that  erase, werase, clear, wclear, clrtobot, and clrtoeol	may be
       macros.

PORTABILITY
       These functions are described in	the XSI	Curses standard, Issue 4.  The
       standard	 specifies  that  they return ERR on failure, but specifies no
       error conditions.

       Some historic curses implementations had, as an	undocumented  feature,
       the  ability  to	 do the	equivalent of clearok(..., 1) by saying	touch-
       win(stdscr) or clear(stdscr).  This will	not work under ncurses.

       This implementation, and	others such as Solaris,	sets the current posi-
       tion  to	0,0 after erasing via werase() and wclear().  That fact	is not
       documented in other implementations, and	may not	be true	of implementa-
       tions which were	not derived from SVr4 source.

       Not obvious from	the description, most implementations clear the	screen
       after wclear even for a subwindow or derived window.   If  you  do  not
       want  to	clear the screen during	the next wrefresh, use werase instead.

SEE ALSO
       curses(3X), curs_outopts(3X), curs_refresh(3X)

								curs_clear(3X)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | NOTES | PORTABILITY | SEE ALSO

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