<!-- 
  ****************************************************************************
  * Copyright (c) 1998-2008,2010 Free Software Foundation, Inc.              *
  *                                                                          *
  * Permission is hereby granted, free of charge, to any person obtaining a  *
  * copy of this software and associated documentation files (the            *
  * "Software"), to deal in the Software without restriction, including      *
  * without limitation the rights to use, copy, modify, merge, publish,      *
  * distribute, distribute with modifications, sublicense, and/or sell       *
  * copies of the Software, and to permit persons to whom the Software is    *
  * furnished to do so, subject to the following conditions:                 *
  *                                                                          *
  * The above copyright notice and this permission notice shall be included  *
  * in all copies or substantial portions of the Software.                   *
  *                                                                          *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
  * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
  * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
  *                                                                          *
  * Except as contained in this notice, the name(s) of the above copyright   *
  * holders shall not be used in advertising or otherwise to promote the     *
  * sale, use or other dealings in this Software without prior written       *
  * authorization.                                                           *
  ****************************************************************************
  * @Id: menu_driver.3x,v 1.20 2010/12/04 18:38:55 tom Exp @
-->
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN">
<HTML>
<HEAD>
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
<meta name="generator" content="Manpage converted by man2html - see http://invisible-island.net/scripts/readme.html#others_scripts">
<TITLE>menu_driver 3x</TITLE>
<link rev=made href="mailto:bug-ncurses@gnu.org">
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
</HEAD>
<BODY>
<H1 class="no-header">menu_driver 3x</H1>
<PRE>
<STRONG><A HREF="menu_driver.3x.html">menu_driver(3x)</A></STRONG>                                         <STRONG><A HREF="menu_driver.3x.html">menu_driver(3x)</A></STRONG>


</PRE>
<H2><a name="h2-NAME">NAME</a></H2><PRE>
       <STRONG>menu_driver</STRONG> - command-processing loop of the menu system


</PRE>
<H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
       <STRONG>#include</STRONG> <STRONG>&lt;menu.h&gt;</STRONG>
       int menu_driver(MENU *menu, int c);


</PRE>
<H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
       Once a menu has been posted (displayed), you should funnel
       input events to it through <STRONG>menu_driver</STRONG>.  This routine  has
       three major input cases:

       <STRONG>o</STRONG>   The  input  is  a form navigation request.  Navigation
           request codes are constants defined in <STRONG>&lt;form.h&gt;</STRONG>, which
           are   distinct  from  the  key-  and  character  codes
           returned by <STRONG>wgetch</STRONG>.

       <STRONG>o</STRONG>   The input is a printable character.  Printable charac-
           ters  (which  must  be  positive,  less  than 256) are
           checked according to the program's locale settings.

       <STRONG>o</STRONG>   The input is the KEY_MOUSE special key associated with
           an mouse event.

       The menu driver requests are as follows:

       REQ_LEFT_ITEM
            Move left to an item.

       REQ_RIGHT_ITEM
            Move right to an item.

       REQ_UP_ITEM
            Move up to an item.

       REQ_DOWN_ITEM
            Move down to an item.

       REQ_SCR_ULINE
            Scroll up a line.

       REQ_SCR_DLINE
            Scroll down a line.

       REQ_SCR_DPAGE
            Scroll down a page.

       REQ_SCR_UPAGE
            Scroll up a page.

       REQ_FIRST_ITEM
            Move to the first item.

       REQ_LAST_ITEM
            Move to the last item.

       REQ_NEXT_ITEM
            Move to the next item.

       REQ_PREV_ITEM
            Move to the previous item.

       REQ_TOGGLE_ITEM
            Select/deselect an item.

       REQ_CLEAR_PATTERN
            Clear the menu pattern buffer.

       REQ_BACK_PATTERN
            Delete  the  previous character from the pattern buf-
            fer.

       REQ_NEXT_MATCH
            Move to the next item matching the pattern match.

       REQ_PREV_MATCH
            Move to the previous item matching the pattern match.

       If the second argument is a printable character, the  code
       appends  it  to the pattern buffer and attempts to move to
       the next item matching the new pattern.  If  there  is  no
       such match, <STRONG>menu_driver</STRONG> returns <STRONG>E_NO_MATCH</STRONG> and deletes the
       appended character from the buffer.

       If the second argument is one  of  the  above  pre-defined
       requests, the corresponding action is performed.


</PRE>
<H3><a name="h3-MOUSE-HANDLING">MOUSE HANDLING</a></H3><PRE>
       If  the  second argument is the KEY_MOUSE special key, the
       associated mouse event is translated into one of the above
       pre-defined  requests.   Currently only clicks in the user
       window (e.g., inside the menu display area or the  decora-
       tion window) are handled.

       If you click above the display region of the menu:

       <STRONG>o</STRONG>   a REQ_SCR_ULINE is generated for a single click,

       <STRONG>o</STRONG>   a REQ_SCR_UPAGE is generated for a double-click and

       <STRONG>o</STRONG>   a REQ_FIRST_ITEM is generated for a triple-click.

       If you click below the display region of the menu:

       <STRONG>o</STRONG>   a REQ_SCR_DLINE is generated for a single click,

       <STRONG>o</STRONG>   a REQ_SCR_DPAGE is generated for a double-click and

       <STRONG>o</STRONG>   a REQ_LAST_ITEM is generated for a triple-click.

       If  you  click  at  an item inside the display area of the
       menu:

       <STRONG>o</STRONG>   the menu cursor is positioned to that item.

       <STRONG>o</STRONG>   If you double-click an item a REQ_TOGGLE_ITEM is  gen-
           erated and <STRONG>E_UNKNOWN_COMMAND</STRONG> is returned.  This return
           value makes sense,  because  a  double  click  usually
           means that an item-specific action should be returned.
           It is exactly the purpose of this return value to sig-
           nal  that  an  application  specific command should be
           executed.

       <STRONG>o</STRONG>   If a translation into a request was done,  <STRONG>menu_driver</STRONG>
           returns the result of this request.

       If  you clicked outside the user window or the mouse event
       could  not  be  translated  into   a   menu   request   an
       <STRONG>E_REQUEST_DENIED</STRONG> is returned.


</PRE>
<H3><a name="h3-APPLICATION-DEFINED-COMMANDS">APPLICATION-DEFINED COMMANDS</a></H3><PRE>
       If the second argument is neither printable nor one of the
       above pre-defined menu requests or  KEY_MOUSE,  the  drive
       assumes  it is an application-specific command and returns
       <STRONG>E_UNKNOWN_COMMAND</STRONG>.  Application-defined commands should be
       defined  relative  to  <STRONG>MAX_COMMAND</STRONG>,  the  maximum value of
       these pre-defined requests.


</PRE>
<H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
       <STRONG>menu_driver</STRONG> return one of the following error codes:

       <STRONG>E_OK</STRONG> The routine succeeded.

       <STRONG>E_SYSTEM_ERROR</STRONG>
            System error occurred (see <STRONG>errno</STRONG>).

       <STRONG>E_BAD_ARGUMENT</STRONG>
            Routine detected an incorrect or  out-of-range  argu-
            ment.

       <STRONG>E_BAD_STATE</STRONG>
            Routine was called from an initialization or termina-
            tion function.

       <STRONG>E_NOT_POSTED</STRONG>
            The menu has not been posted.

       <STRONG>E_UNKNOWN_COMMAND</STRONG>
            The menu driver code saw an unknown request code.

       <STRONG>E_NO_MATCH</STRONG>
            Character failed to match.

       <STRONG>E_REQUEST_DENIED</STRONG>
            The menu driver could not process the request.


</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="menu.3x.html">menu(3x)</A></STRONG>, <STRONG><A HREF="curs_getch.3x.html">curs_getch(3x)</A></STRONG>.


</PRE>
<H2><a name="h2-NOTES">NOTES</a></H2><PRE>
       The header file <STRONG>&lt;menu.h&gt;</STRONG> automatically includes the header
       files <STRONG>&lt;curses.h&gt;</STRONG>.


</PRE>
<H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
       These  routines  emulate  the System V menu library.  They
       were not supported on Version 7 or BSD versions. The  sup-
       port for mouse events is ncurses specific.


</PRE>
<H2><a name="h2-AUTHORS">AUTHORS</a></H2><PRE>
       Juergen  Pfeifer.   Manual  pages  and  adaptation for new
       curses by Eric S. Raymond.


                                                        <STRONG><A HREF="menu_driver.3x.html">menu_driver(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-MOUSE-HANDLING">MOUSE HANDLING</a></li>
<li><a href="#h3-APPLICATION-DEFINED-COMMANDS">APPLICATION-DEFINED COMMANDS</a></li>
</ul>
</li>
<li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li>
<li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>
<li><a href="#h2-NOTES">NOTES</a></li>
<li><a href="#h2-PORTABILITY">PORTABILITY</a></li>
<li><a href="#h2-AUTHORS">AUTHORS</a></li>
</ul>
</div>
</BODY>
</HTML>