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<H1 class="no-header">curs_clear 3x</H1>
<PRE>
<STRONG><A HREF="curs_clear.3x.html">curs_clear(3x)</A></STRONG>                                                  <STRONG><A HREF="curs_clear.3x.html">curs_clear(3x)</A></STRONG>


</PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
       <STRONG>erase</STRONG>, <STRONG>werase</STRONG>, <STRONG>clear</STRONG>, <STRONG>wclear</STRONG>, <STRONG>clrtobot</STRONG>, <STRONG>wclrtobot</STRONG>, <STRONG>clrtoeol</STRONG>, <STRONG>wclrtoeol</STRONG>
       - clear all or part of a <STRONG>curses</STRONG> window


</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
       <STRONG>#</STRONG> <STRONG>include</STRONG> <STRONG>&lt;curses.h&gt;</STRONG>

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


</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
       The <STRONG>erase</STRONG> and <STRONG>werase</STRONG> routines copy blanks to every position in the win-
       dow, clearing the screen.

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

       The <STRONG>clrtobot</STRONG> and <STRONG>wclrtobot</STRONG> 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 <STRONG>clrtoeol</STRONG> and <STRONG>wclrtoeol</STRONG> 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 <STRONG>wbkgdset</STRONG>) merged into them.


</PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
       All routines return the integer <STRONG>OK</STRONG> on success and <STRONG>ERR</STRONG> on failure.   The
       SVr4.0  manual  says "or a non-negative integer if <STRONG>immedok</STRONG> 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.


</PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
       Note  that  <STRONG>erase</STRONG>, <STRONG>werase</STRONG>, <STRONG>clear</STRONG>, <STRONG>wclear</STRONG>, <STRONG>clrtobot</STRONG>, and <STRONG>clrtoeol</STRONG> may be
       macros.


</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
       These functions are described in the XSI Curses standard, Issue 4.  The
       standard  specifies  that  they return <STRONG>ERR</STRONG> on failure, but specifies no
       error conditions.

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

       This implementation, and others such as Solaris, sets the current posi-
       tion to 0,0 after erasing via <STRONG>werase</STRONG> and <STRONG>wclear</STRONG>.  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 <STRONG>wclear</STRONG> even for a subwindow or derived window.   If  you  do  not
       want to clear the screen during the next <STRONG>wrefresh</STRONG>, use <STRONG>werase</STRONG> instead.


</PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
       <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>, <STRONG><A HREF="curs_outopts.3x.html">curs_outopts(3x)</A></STRONG>, <STRONG><A HREF="curs_refresh.3x.html">curs_refresh(3x)</A></STRONG>, <STRONG><A HREF="curs_variables.3x.html">curs_variables(3x)</A></STRONG>


                                                                <STRONG><A HREF="curs_clear.3x.html">curs_clear(3x)</A></STRONG>
</PRE>
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<ul>
<li><a href="#h2-NAME">NAME</a></li>
<li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
<li><a href="#h2-DESCRIPTION">DESCRIPTION</a></li>
<li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li>
<li><a href="#h2-NOTES">NOTES</a></li>
<li><a href="#h2-PORTABILITY">PORTABILITY</a></li>
<li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>
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