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




</PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
       <STRONG>doupdate</STRONG>, <STRONG>redrawwin</STRONG>, <STRONG>refresh</STRONG>, <STRONG>wnoutrefresh</STRONG>, <STRONG>wredrawln</STRONG>, <STRONG>wrefresh</STRONG> -
       refresh <STRONG>curses</STRONG> windows and lines


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

       <STRONG>int</STRONG> <STRONG>refresh(void);</STRONG>
       <STRONG>int</STRONG> <STRONG>wrefresh(WINDOW</STRONG> <STRONG>*win);</STRONG>
       <STRONG>int</STRONG> <STRONG>wnoutrefresh(WINDOW</STRONG> <STRONG>*win);</STRONG>
       <STRONG>int</STRONG> <STRONG>doupdate(void);</STRONG>
       <STRONG>int</STRONG> <STRONG>redrawwin(WINDOW</STRONG> <STRONG>*win);</STRONG>
       <STRONG>int</STRONG> <STRONG>wredrawln(WINDOW</STRONG> <STRONG>*win,</STRONG> <STRONG>int</STRONG> <STRONG>beg_line,</STRONG> <STRONG>int</STRONG> <STRONG>num_lines);</STRONG>


</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>

</PRE><H3><a name="h3-refresh_wrefresh">refresh/wrefresh</a></H3><PRE>
       The <STRONG>refresh</STRONG> and <STRONG>wrefresh</STRONG> routines (or <STRONG>wnoutrefresh</STRONG> and  <STRONG>doupdate</STRONG>)  must
       be called to get actual output to the terminal, as other routines mere-
       ly manipulate data structures.  The routine <STRONG>wrefresh</STRONG> copies  the  named
       window  to  the  <EM>physical</EM>  <EM>screen</EM>,  taking into account what is already
       there to do optimizations.  The <STRONG>refresh</STRONG> routine is the same, using <STRONG>std-</STRONG>
       <STRONG>scr</STRONG> as the default window.  Unless <STRONG>leaveok</STRONG> has been enabled, the physi-
       cal cursor of the terminal is left at the location of  the  cursor  for
       that window.


</PRE><H3><a name="h3-wnoutrefresh_doupdate">wnoutrefresh/doupdate</a></H3><PRE>
       The <STRONG>wnoutrefresh</STRONG> and <STRONG>doupdate</STRONG> routines allow multiple updates with more
       efficiency than <STRONG>wrefresh</STRONG> alone.  In addition to all the  window  struc-
       tures,  <STRONG>curses</STRONG>  keeps  two  data  structures  representing the terminal
       screen:

       <STRONG>o</STRONG>   a <EM>physical</EM> <EM>screen</EM>, describing what is actually on the screen, and

       <STRONG>o</STRONG>   a <EM>virtual</EM> <EM>screen</EM>, describing what the programmer wants to  have  on
           the screen.

       The routine <STRONG>wrefresh</STRONG> works by

       <STRONG>o</STRONG>   first  calling  <STRONG>wnoutrefresh</STRONG>,  which copies the named window to the
           <EM>virtual</EM> <EM>screen</EM>, and

       <STRONG>o</STRONG>   then calling <STRONG>doupdate</STRONG>, which compares the  <EM>virtual</EM>  <EM>screen</EM>  to  the
           <EM>physical</EM> <EM>screen</EM> and does the actual update.

       If the programmer wishes to output several windows at once, a series of
       calls to <STRONG>wrefresh</STRONG> results in  alternating  calls  to  <STRONG>wnoutrefresh</STRONG>  and
       <STRONG>doupdate</STRONG>,  causing  several  bursts  of output to the screen.  By first
       calling <STRONG>wnoutrefresh</STRONG> for each window, it is then possible to call <STRONG>doup-</STRONG>
       <STRONG>date</STRONG>  once,  resulting  in  only  one burst of output, with fewer total
       characters transmitted and less CPU time used.

       If the <EM>win</EM> argument to <STRONG>wrefresh</STRONG> is the <EM>physical</EM> <EM>screen</EM> (i.e., the glob-
       al  variable  <STRONG>curscr</STRONG>),  the screen is immediately cleared and repainted
       from scratch.

       The phrase "copies the named window to the virtual screen" above is am-
       biguous.   What actually happens is that all <EM>touched</EM> (changed) lines in
       the window are copied to the virtual  screen.   This  affects  programs
       that use overlapping windows; it means that if two windows overlap, you
       can refresh them in either order and the overlap region will  be  modi-
       fied  only  when  it  is  explicitly  changed.  (But see the section on
       <STRONG>PORTABILITY</STRONG> below for a warning about exploiting this behavior.)


</PRE><H3><a name="h3-wredrawln_redrawwin">wredrawln/redrawwin</a></H3><PRE>
       The <STRONG>wredrawln</STRONG> routine indicates to <STRONG>curses</STRONG> that some  screen  lines  are
       corrupted  and  should  be  thrown away before anything is written over
       them.  It touches the indicated lines (marking them changed).  The rou-
       tine <STRONG>redrawwin</STRONG> touches the entire window.


</PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
       Routines  that  return an integer return <STRONG>ERR</STRONG> upon failure, and <STRONG>OK</STRONG> (SVr4
       only specifies "an integer value other than <STRONG>ERR</STRONG>") upon successful  com-
       pletion.

       X/Open does not define any error conditions.  In this implementation

          <STRONG>wnoutrefresh</STRONG>
               returns  an error if the window pointer is null, or if the win-
               dow is really a pad.

          <STRONG>wredrawln</STRONG>
               returns an error if the associated call to <STRONG>touchln</STRONG>  returns  an
               error.


</PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
       Note that <STRONG>refresh</STRONG> and <STRONG>redrawwin</STRONG> may be macros.


</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
       The XSI Curses standard, Issue 4 describes these functions.

       Whether  <STRONG>wnoutrefresh</STRONG>  copies to the virtual screen the entire contents
       of a window or just its changed portions has never been well-documented
       in  historic  curses  versions (including SVr4).  It might be unwise to
       rely on either behavior in programs that might have to be  linked  with
       other curses implementations.  Instead, you can do an explicit <STRONG>touchwin</STRONG>
       before the <STRONG>wnoutrefresh</STRONG> call to guarantee an entire-contents copy  any-
       where.


</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_variables.3x.html">curs_variables(3x)</A></STRONG>.



                                                              <STRONG><A HREF="curs_refresh.3x.html">curs_refresh(3x)</A></STRONG>
</PRE>
<div class="nav">
<ul>
<li><a href="#h2-NAME">NAME</a></li>
<li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
<li><a href="#h2-DESCRIPTION">DESCRIPTION</a>
<ul>
<li><a href="#h3-refresh_wrefresh">refresh/wrefresh</a></li>
<li><a href="#h3-wnoutrefresh_doupdate">wnoutrefresh/doupdate</a></li>
<li><a href="#h3-wredrawln_redrawwin">wredrawln/redrawwin</a></li>
</ul>
</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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