MirOS Manual: clear(3), clrtobot(3), clrtoeol(3), curs_clear(3), erase(3), wclear(3), wclrtobot(3), wclrtoeol(3), werase(3)


curs_clear(3)       UNIX Programmer's Manual        curs_clear(3)

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 com-
     pletely 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 rendi-
     tion (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,

MirOS BSD #10-current  Printed 03.04.2017                       1

curs_clear(3)       UNIX Programmer's Manual        curs_clear(3)

     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  implementa-
     tions, and may not be true of implementations which were not
     derived from SVr4 source.

SEE ALSO

     curses(3), curs_outopts(3), curs_refresh(3)

MirOS BSD #10-current  Printed 03.04.2017                       2

Generated on 2017-04-03 16:26:17 by $MirOS: src/scripts/roff2htm,v 1.88 2017/01/29 00:51:06 tg Exp $

These manual pages and other documentation are copyrighted by their respective writers; their source is available at our CVSweb, AnonCVS, and other mirrors. The rest is Copyright © 2002–2017 The MirOS Project, Germany.
This product includes material provided by mirabilos.

This manual page’s HTML representation is supposed to be valid XHTML/1.1; if not, please send a bug report — diffs preferred.