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-<H1>curs_clear 3x</H1>
-<HR>
+<H1 class="no-header">curs_clear 3X</H1>
<PRE>
-<!-- Manpage converted by man2html 3.0.1 -->
-<STRONG><A HREF="curs_clear.3x.html">curs_clear(3x)</A></STRONG> <STRONG><A HREF="curs_clear.3x.html">curs_clear(3x)</A></STRONG>
+<B><A HREF="curs_clear.3X.html">curs_clear(3X)</A></B> <B><A HREF="curs_clear.3X.html">curs_clear(3X)</A></B>
-</PRE>
-<H2>NAME</H2><PRE>
- <STRONG>erase</STRONG>, <STRONG>werase</STRONG>, <STRONG>clear</STRONG>, <STRONG>wclear</STRONG>, <STRONG>clrtobot</STRONG>, <STRONG>wclrtobot</STRONG>, <STRONG>clr-</STRONG>
- <STRONG>toeol</STRONG>, <STRONG>wclrtoeol</STRONG> - clear all or part of a <STRONG>curses</STRONG> window
+</PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
+ <B>erase</B>, <B>werase</B>, <B>clear</B>, <B>wclear</B>, <B>clrtobot</B>, <B>wclrtobot</B>, <B>clrtoeol</B>, <B>wclrtoeol</B>
+ - clear all or part of a <B>curses</B> window
-</PRE>
-<H2>SYNOPSIS</H2><PRE>
- <STRONG>#</STRONG> <STRONG>include</STRONG> <STRONG><curses.h></STRONG>
+</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
+ <B>#include</B> <B><curses.h></B>
- <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>
+ <B>int</B> <B>erase(void);</B>
+ <B>int</B> <B>werase(WINDOW</B> <B>*</B><I>win</I><B>);</B>
+ <B>int</B> <B>clear(void);</B>
+ <B>int</B> <B>wclear(WINDOW</B> <B>*</B><I>win</I><B>);</B>
-</PRE>
-<H2>DESCRIPTION</H2><PRE>
- The <STRONG>erase</STRONG> and <STRONG>werase</STRONG> routines copy blanks to every posi-
- tion in the window, clearing the screen.
+ <B>int</B> <B>clrtobot(void);</B>
+ <B>int</B> <B>wclrtobot(WINDOW</B> <B>*</B><I>win</I><B>);</B>
- 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.
+ <B>int</B> <B>clrtoeol(void);</B>
+ <B>int</B> <B>wclrtoeol(WINDOW</B> <B>*</B><I>win</I><B>);</B>
- 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.
+</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
+ The <B>erase</B> and <B>werase</B> routines copy blanks to every position in the win-
+ dow, clearing the screen.
- Blanks created by erasure have the current background ren-
- dition (as set by <STRONG>wbkgdset</STRONG>) merged into them.
+ The <B>clear</B> and <B>wclear</B> routines are like <B>erase</B> and <B>werase</B>, but they also
+ call <B>clearok</B>, so that the screen is cleared completely on the next call
+ to <B>wrefresh</B> for that window and repainted from scratch.
+ The <B>clrtobot</B> and <B>wclrtobot</B> 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.
-</PRE>
-<H2>RETURN VALUE</H2><PRE>
- All routines return the integer <STRONG>OK</STRONG>. The SVr4.0 manual
- says "or a non-negative integer if <STRONG>immedok</STRONG> is set", but
- this appears to be an error.
+ The <B>clrtoeol</B> and <B>wclrtoeol</B> 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 <B>wbkgdset</B>) merged into them.
-</PRE>
-<H2>NOTES</H2><PRE>
- Note that <STRONG>erase</STRONG>, <STRONG>werase</STRONG>, <STRONG>clear</STRONG>, <STRONG>wclear</STRONG>, <STRONG>clrtobot</STRONG>, and <STRONG>clr-</STRONG>
- <STRONG>toeol</STRONG> may be macros.
+</PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
+ All routines return the integer <B>OK</B> on success and <B>ERR</B> on failure.
-</PRE>
-<H2>PORTABILITY</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.
+ X/Open defines no error conditions. In this implementation,
- Some historic curses implementations had, as an undocu-
- mented feature, the ability to do the equivalent of
- <STRONG>clearok(...,</STRONG> <STRONG>1)</STRONG> by saying <STRONG>touchwin(stdscr)</STRONG> or <STRONG>clear(std-</STRONG>
- <STRONG>scr)</STRONG>. This will not work under ncurses.
+ <B>o</B> functions using a window pointer parameter return an error if it is
+ null
+ <B>o</B> <B>wclrtoeol</B> returns an error if the cursor position is about to wrap.
-</PRE>
-<H2>SEE ALSO</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>
+
+</PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
+ Note that <B>erase</B>, <B>werase</B>, <B>clear</B>, <B>wclear</B>, <B>clrtobot</B>, and <B>clrtoeol</B> 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 <B>ERR</B> on failure, but specifies no
+ error conditions.
+
+ The SVr4.0 manual says that these functions could return "a non-nega-
+ tive integer if <B>immedok</B> is set", referring to the return-value of <B>wre-</B>
+ <B>fresh</B>. In that implementation, <B>wrefresh</B> would return a count of the
+ number of characters written to the terminal.
+
+ Some historic curses implementations had, as an undocumented feature,
+ the ability to do the equivalent of <B>clearok(...,</B> <B>1)</B> by saying <B>touch-</B>
+ <B>win(stdscr)</B> or <B>clear(stdscr)</B>. This will not work under ncurses.
+
+ This implementation, and others such as Solaris, sets the current posi-
+ tion to 0,0 after erasing via <B>werase</B> and <B>wclear</B>. 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 <B>wclear</B> even for a subwindow or derived window. If you do not
+ want to clear the screen during the next <B>wrefresh</B>, use <B>werase</B> instead.
+
+
+</PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
+ <B><A HREF="curses.3X.html">curses(3X)</A></B>, <B><A HREF="curs_outopts.3X.html">curs_outopts(3X)</A></B>, <B><A HREF="curs_refresh.3X.html">curs_refresh(3X)</A></B>, <B><A HREF="curs_variables.3X.html">curs_variables(3X)</A></B>
- <STRONG><A HREF="curs_clear.3x.html">curs_clear(3x)</A></STRONG>
+ <B><A HREF="curs_clear.3X.html">curs_clear(3X)</A></B>
</PRE>
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-<ADDRESS>
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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>
+</ul>
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