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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  window,  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 re-
       painted 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, in-
       clusive, 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 touchwin(stdscr) or clear(stdscr).	This will
       not work under ncurses.

       This implementation, and others such as Solaris, sets the current position  to  0,0  after
       erasing	via werase() and wclear().  That fact is not documented in other implementations,
       and may not be true of implementations 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_variables(3X)

										   curs_clear(3X)
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