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




</PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
       <STRONG>is_term_resized</STRONG>,  <STRONG>resize_term</STRONG>,  <STRONG>resizeterm</STRONG> - change the curses terminal
       size


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

       <STRONG>bool</STRONG> <STRONG>is_term_resized(int</STRONG> <STRONG>lines,</STRONG> <STRONG>int</STRONG> <STRONG>columns);</STRONG>
       <STRONG>int</STRONG> <STRONG>resize_term(int</STRONG> <STRONG>lines,</STRONG> <STRONG>int</STRONG> <STRONG>columns);</STRONG>
       <STRONG>int</STRONG> <STRONG>resizeterm(int</STRONG> <STRONG>lines,</STRONG> <STRONG>int</STRONG> <STRONG>columns);</STRONG>


</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
       This is an extension to the curses library.  It provides callers with a
       hook into the <STRONG>ncurses</STRONG> data to resize windows, primarily for use by pro-
       grams running in an X Window terminal (e.g., xterm).


</PRE><H3><a name="h3-resizeterm">resizeterm</a></H3><PRE>
       The function <STRONG>resizeterm</STRONG> resizes the standard and current windows to the
       specified  dimensions,  and  adjusts other bookkeeping data used by the
       <STRONG>ncurses</STRONG> library that record the window dimensions such as the <STRONG>LINES</STRONG> and
       <STRONG>COLS</STRONG> variables.


</PRE><H3><a name="h3-resize_term">resize_term</a></H3><PRE>
       Most  of the work is done by the inner function <STRONG>resize_term</STRONG>.  The outer
       function <STRONG>resizeterm</STRONG> adds bookkeeping for the <STRONG>SIGWINCH</STRONG> handler, as  well
       as repainting the soft-key area (see <STRONG><A HREF="slk_touch.3x.html">slk_touch(3x)</A></STRONG>).

       When  resizing  the windows, <STRONG>resize_term</STRONG> blank-fills the areas that are
       extended.  The calling application should  fill  in  these  areas  with
       appropriate data.

       The  <STRONG>resize_term</STRONG> function attempts to resize all windows.  However, due
       to the calling convention of pads, it is not possible to  resize  these
       without additional interaction with the application.

       When  resizing  windows,  <STRONG>resize_term</STRONG>  recursively  adjusts subwindows,
       keeping them within the updated parent window's limits.  If a top-level
       window  happens  to extend to the screen's limits, then on resizing the
       window, <STRONG>resize_term</STRONG> will keep the window extending to the corresponding
       limit, regardless of whether the screen has shrunk or grown.


</PRE><H3><a name="h3-is_term_resized">is_term_resized</a></H3><PRE>
       A support function <STRONG>is_term_resized</STRONG> is provided so that applications can
       check if the <STRONG>resize_term</STRONG> function would modify the  window  structures.
       It returns <STRONG>TRUE</STRONG> if the windows would be modified, and <STRONG>FALSE</STRONG> otherwise.


</PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
       Except  as  noted,  these functions return the integer <STRONG>ERR</STRONG> upon failure
       and <STRONG>OK</STRONG> on success.  They will fail if either of the dimensions are less
       than  or equal to zero, or if an error occurs while (re)allocating mem-
       ory for the windows.


</PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
       While these functions are intended to be used to support a signal  han-
       dler  (i.e., for <STRONG>SIGWINCH</STRONG>), care should be taken to avoid invoking them
       in a context where <STRONG>malloc</STRONG> or <STRONG>realloc</STRONG> may have been  interrupted,  since
       it uses those functions.

       If ncurses is configured to supply its own <STRONG>SIGWINCH</STRONG> handler,

       <STRONG>o</STRONG>   on receipt of a <STRONG>SIGWINCH</STRONG>, the handler sets a flag

       <STRONG>o</STRONG>   which is tested in <STRONG><A HREF="curs_getch.3x.html">wgetch(3x)</A></STRONG> and <STRONG>doupdate</STRONG>,

       <STRONG>o</STRONG>   in turn, calling the <STRONG>resizeterm</STRONG> function,

       <STRONG>o</STRONG>   which <STRONG>ungetch</STRONG>'s a <STRONG>KEY_RESIZE</STRONG> which will be read on the next call to
           <STRONG>wgetch</STRONG>.

           The <STRONG>KEY_RESIZE</STRONG> alerts an  application  that  the  screen  size  has
           changed,  and  that it should repaint special features such as pads
           that cannot be done automatically.

           Calling <STRONG>resizeterm</STRONG> or <STRONG>resize_term</STRONG> directly from a signal handler is
           unsafe.   This  indirect  method  is  used to provide a safe way to
           resize the ncurses data structures.

       If the environment variables <STRONG>LINES</STRONG> or <STRONG>COLUMNS</STRONG> are set,  this  overrides
       the  library's  use of the window size obtained from the operating sys-
       tem.  Thus, even if a <STRONG>SIGWINCH</STRONG> is received, no screen size  change  may
       be recorded.


</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
       It is possible to resize the screen with SVr4 curses, by

       <STRONG>o</STRONG>   exiting curses with <STRONG><A HREF="curs_initscr.3x.html">endwin(3x)</A></STRONG> and

       <STRONG>o</STRONG>   resuming using <STRONG><A HREF="curs_refresh.3x.html">refresh(3x)</A></STRONG>.

       Doing that clears the screen and is visually distracting.

       This  extension  of ncurses was introduced in mid-1995.  It was adopted
       in NetBSD curses (2001) and PDCurses (2003).


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


</PRE><H2><a name="h2-AUTHOR">AUTHOR</a></H2><PRE>
       Thomas Dickey (from an equivalent function  written  in  1988  for  BSD
       curses).



                                                                <STRONG><A HREF="resizeterm.3x.html">resizeterm(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-resizeterm">resizeterm</a></li>
<li><a href="#h3-resize_term">resize_term</a></li>
<li><a href="#h3-is_term_resized">is_term_resized</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>
<li><a href="#h2-AUTHOR">AUTHOR</a></li>
</ul>
</div>
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