curs_clear 3x

curs_clear(3x)                                                  curs_clear(3x)


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


       # 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);


       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

       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.


       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.


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


       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 doc-
       umented 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.


       curses(3x), curs_outopts(3x), curs_refresh(3x), curs_variables(3x)