diff options
author | rafan <rafan@FreeBSD.org> | 2007-01-20 07:32:02 +0000 |
---|---|---|
committer | rafan <rafan@FreeBSD.org> | 2007-01-20 07:32:02 +0000 |
commit | a35ca3ffa07d253f729abfe49e019438658f9333 (patch) | |
tree | 1351fbc560fb430cd5e493287f4950d583f23af3 /contrib/ncurses/doc/html | |
parent | 61ebc4fdc6ffaff63296473b0fef0ff5e17067f7 (diff) | |
parent | de9cbef68d4c3ea6cd003ce086e2d3487600ace7 (diff) | |
download | FreeBSD-src-a35ca3ffa07d253f729abfe49e019438658f9333.zip FreeBSD-src-a35ca3ffa07d253f729abfe49e019438658f9333.tar.gz |
This commit was generated by cvs2svn to compensate for changes in r166124,
which included commits to RCS files with non-trunk default branches.
Diffstat (limited to 'contrib/ncurses/doc/html')
-rw-r--r-- | contrib/ncurses/doc/html/NCURSES-Programming-HOWTO.html | 6413 | ||||
-rw-r--r-- | contrib/ncurses/doc/html/announce.html | 627 | ||||
-rw-r--r-- | contrib/ncurses/doc/html/hackguide.html | 38 | ||||
-rw-r--r-- | contrib/ncurses/doc/html/ncurses-intro.html | 66 |
4 files changed, 6806 insertions, 338 deletions
diff --git a/contrib/ncurses/doc/html/NCURSES-Programming-HOWTO.html b/contrib/ncurses/doc/html/NCURSES-Programming-HOWTO.html new file mode 100644 index 0000000..3a10106 --- /dev/null +++ b/contrib/ncurses/doc/html/NCURSES-Programming-HOWTO.html @@ -0,0 +1,6413 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> +<html> +<head> +<meta name="generator" content= +"HTML Tidy for Linux/x86 (vers 1st December 2004), see www.w3.org"> +<title>NCURSES Programming HOWTO</title> +<meta name="GENERATOR" content= +"Modular DocBook HTML Stylesheet Version 1.7"> +</head> +<body class="ARTICLE" bgcolor="#FFFFFF" text="#000000" link= +"#0000FF" vlink="#840084" alink="#0000FF"> +<div class="ARTICLE"> +<div class="TITLEPAGE"> +<h1 class="TITLE"><a name="AEN2" id="AEN2">NCURSES Programming +HOWTO</a></h1> +<h3 class="AUTHOR"><a name="AEN4" id="AEN4">Pradeep Padala</a></h3> +<div class="AFFILIATION"> +<div class="ADDRESS"> +<p class="ADDRESS"><code class="EMAIL"><<a href= +"mailto:ppadala@gmail.com">ppadala@gmail.com</a>></code></p> +</div> +</div> +<p class="PUBDATE">v1.9, 2005-06-20<br></p> +<div class="REVHISTORY"> +<table width="100%" border="0"> +<tr> +<th align="left" valign="top" colspan="3"><b>Revision +History</b></th> +</tr> +<tr> +<td align="left">Revision 1.9</td> +<td align="left">2005-06-20</td> +<td align="left">Revised by: ppadala</td> +</tr> +<tr> +<td align="left" colspan="3">The license has been changed to the +MIT-style license used by NCURSES. Note that the programs are also +re-licensed under this.</td> +</tr> +<tr> +<td align="left">Revision 1.8</td> +<td align="left">2005-06-17</td> +<td align="left">Revised by: ppadala</td> +</tr> +<tr> +<td align="left" colspan="3">Lots of updates. Added references and +perl examples. Changes to examples. Many grammatical and stylistic +changes to the content. Changes to NCURSES history.</td> +</tr> +<tr> +<td align="left">Revision 1.7.1</td> +<td align="left">2002-06-25</td> +<td align="left">Revised by: ppadala</td> +</tr> +<tr> +<td align="left" colspan="3">Added a README file for building and +instructions for building from source.</td> +</tr> +<tr> +<td align="left">Revision 1.7</td> +<td align="left">2002-06-25</td> +<td align="left">Revised by: ppadala</td> +</tr> +<tr> +<td align="left" colspan="3">Added "Other formats" section and made +a lot of fancy changes to the programs. Inlining of programs is +gone.</td> +</tr> +<tr> +<td align="left">Revision 1.6.1</td> +<td align="left">2002-02-24</td> +<td align="left">Revised by: ppadala</td> +</tr> +<tr> +<td align="left" colspan="3">Removed the old Changelog section, +cleaned the makefiles</td> +</tr> +<tr> +<td align="left">Revision 1.6</td> +<td align="left">2002-02-16</td> +<td align="left">Revised by: ppadala</td> +</tr> +<tr> +<td align="left" colspan="3">Corrected a lot of spelling mistakes, +added ACS variables section</td> +</tr> +<tr> +<td align="left">Revision 1.5</td> +<td align="left">2002-01-05</td> +<td align="left">Revised by: ppadala</td> +</tr> +<tr> +<td align="left" colspan="3">Changed structure to present proper +TOC</td> +</tr> +<tr> +<td align="left">Revision 1.3.1</td> +<td align="left">2001-07-26</td> +<td align="left">Revised by: ppadala</td> +</tr> +<tr> +<td align="left" colspan="3">Corrected maintainers paragraph, +Corrected stable release number</td> +</tr> +<tr> +<td align="left">Revision 1.3</td> +<td align="left">2001-07-24</td> +<td align="left">Revised by: ppadala</td> +</tr> +<tr> +<td align="left" colspan="3">Added copyright notices to main +document (LDP license) and programs (GPL), Corrected +printw_example.</td> +</tr> +<tr> +<td align="left">Revision 1.2</td> +<td align="left">2001-06-05</td> +<td align="left">Revised by: ppadala</td> +</tr> +<tr> +<td align="left" colspan="3">Incorporated ravi's changes. Mainly to +introduction, menu, form, justforfun sections</td> +</tr> +<tr> +<td align="left">Revision 1.1</td> +<td align="left">2001-05-22</td> +<td align="left">Revised by: ppadala</td> +</tr> +<tr> +<td align="left" colspan="3">Added "a word about window" section, +Added scanw_example.</td> +</tr> +</table> +</div> +<div> +<div class="ABSTRACT"><a name="AEN67" id="AEN67"></a> +<p><em>This document is intended to be an "All in One" guide for +programming with ncurses and its sister libraries. We graduate from +a simple "Hello World" program to more complex form manipulation. +No prior experience in ncurses is assumed. Send comments to +<a href="mailto:ppadala@gmail.com" target="_top">this +address</a></em></p> +</div> +</div> +<hr></div> +<div class="TOC"> +<dl> +<dt><b>Table of Contents</b></dt> +<dt>1. <a href="#INTRO">Introduction</a></dt> +<dd> +<dl> +<dt>1.1. <a href="#WHATIS">What is NCURSES?</a></dt> +<dt>1.2. <a href="#WHATCANWEDO">What we can do with +NCURSES</a></dt> +<dt>1.3. <a href="#WHERETOGETIT">Where to get it</a></dt> +<dt>1.4. <a href="#PURPOSE">Purpose/Scope of the document</a></dt> +<dt>1.5. <a href="#ABOUTPROGRAMS">About the Programs</a></dt> +<dt>1.6. <a href="#OTHERFORMATS">Other Formats of the +document</a></dt> +<dt>1.7. <a href="#CREDITS">Credits</a></dt> +<dt>1.8. <a href="#WISHLIST">Wish List</a></dt> +<dt>1.9. <a href="#COPYRIGHT">Copyright</a></dt> +</dl> +</dd> +<dt>2. <a href="#HELLOWORLD">Hello World !!!</a></dt> +<dd> +<dl> +<dt>2.1. <a href="#COMPILECURSES">Compiling With the NCURSES +Library</a></dt> +<dt>2.2. <a href="#DISSECTION">Dissection</a></dt> +</dl> +</dd> +<dt>3. <a href="#GORY">The Gory Details</a></dt> +<dt>4. <a href="#INIT">Initialization</a></dt> +<dd> +<dl> +<dt>4.1. <a href="#ABOUTINIT">Initialization functions</a></dt> +<dt>4.2. <a href="#RAWCBREAK">raw() and cbreak()</a></dt> +<dt>4.3. <a href="#ECHONOECHO">echo() and noecho()</a></dt> +<dt>4.4. <a href="#KEYPAD">keypad()</a></dt> +<dt>4.5. <a href="#HALFDELAY">halfdelay()</a></dt> +<dt>4.6. <a href="#MISCINIT">Miscellaneous Initialization +functions</a></dt> +<dt>4.7. <a href="#INITEX">An Example</a></dt> +</dl> +</dd> +<dt>5. <a href="#AWORDWINDOWS">A Word about Windows</a></dt> +<dt>6. <a href="#PRINTW">Output functions</a></dt> +<dd> +<dl> +<dt>6.1. <a href="#ADDCHCLASS">addch() class of functions</a></dt> +<dt>6.2. <a href="#AEN298">mvaddch(), waddch() and +mvwaddch()</a></dt> +<dt>6.3. <a href="#PRINTWCLASS">printw() class of +functions</a></dt> +<dt>6.4. <a href="#ADDSTRCLASS">addstr() class of +functions</a></dt> +<dt>6.5. <a href="#ACAUTION">A word of caution</a></dt> +</dl> +</dd> +<dt>7. <a href="#SCANW">Input functions</a></dt> +<dd> +<dl> +<dt>7.1. <a href="#GETCHCLASS">getch() class of functions</a></dt> +<dt>7.2. <a href="#SCANWCLASS">scanw() class of functions</a></dt> +<dt>7.3. <a href="#GETSTRCLASS">getstr() class of +functions</a></dt> +<dt>7.4. <a href="#GETSTREX">Some examples</a></dt> +</dl> +</dd> +<dt>8. <a href="#ATTRIB">Attributes</a></dt> +<dd> +<dl> +<dt>8.1. <a href="#ATTRIBDETAILS">The details</a></dt> +<dt>8.2. <a href="#ATTRONVSATTRSET">attron() vs attrset()</a></dt> +<dt>8.3. <a href="#ATTR_GET">attr_get()</a></dt> +<dt>8.4. <a href="#ATTR_FUNCS">attr_ functions</a></dt> +<dt>8.5. <a href="#WATTRFUNCS">wattr functions</a></dt> +<dt>8.6. <a href="#CHGAT">chgat() functions</a></dt> +</dl> +</dd> +<dt>9. <a href="#WINDOWS">Windows</a></dt> +<dd> +<dl> +<dt>9.1. <a href="#WINDOWBASICS">The basics</a></dt> +<dt>9.2. <a href="#LETBEWINDOW">Let there be a Window !!!</a></dt> +<dt>9.3. <a href="#BORDEREXEXPL">Explanation</a></dt> +<dt>9.4. <a href="#OTHERSTUFF">The other stuff in the +example</a></dt> +<dt>9.5. <a href="#OTHERBORDERFUNCS">Other Border +functions</a></dt> +</dl> +</dd> +<dt>10. <a href="#COLOR">Colors</a></dt> +<dd> +<dl> +<dt>10.1. <a href="#COLORBASICS">The basics</a></dt> +<dt>10.2. <a href="#CHANGECOLORDEFS">Changing Color +Definitions</a></dt> +<dt>10.3. <a href="#COLORCONTENT">Color Content</a></dt> +</dl> +</dd> +<dt>11. <a href="#KEYS">Interfacing with the key board</a></dt> +<dd> +<dl> +<dt>11.1. <a href="#KEYSBASICS">The Basics</a></dt> +<dt>11.2. <a href="#SIMPLEKEYEX">A Simple Key Usage +example</a></dt> +</dl> +</dd> +<dt>12. <a href="#MOUSE">Interfacing with the mouse</a></dt> +<dd> +<dl> +<dt>12.1. <a href="#MOUSEBASICS">The Basics</a></dt> +<dt>12.2. <a href="#GETTINGEVENTS">Getting the events</a></dt> +<dt>12.3. <a href="#MOUSETOGETHER">Putting it all Together</a></dt> +<dt>12.4. <a href="#MISCMOUSEFUNCS">Miscellaneous +Functions</a></dt> +</dl> +</dd> +<dt>13. <a href="#SCREEN">Screen Manipulation</a></dt> +<dd> +<dl> +<dt>13.1. <a href="#GETYX">getyx() functions</a></dt> +<dt>13.2. <a href="#SCREENDUMP">Screen Dumping</a></dt> +<dt>13.3. <a href="#WINDOWDUMP">Window Dumping</a></dt> +</dl> +</dd> +<dt>14. <a href="#MISC">Miscellaneous features</a></dt> +<dd> +<dl> +<dt>14.1. <a href="#CURSSET">curs_set()</a></dt> +<dt>14.2. <a href="#TEMPLEAVE">Temporarily Leaving Curses +mode</a></dt> +<dt>14.3. <a href="#ACSVARS">ACS_ variables</a></dt> +</dl> +</dd> +<dt>15. <a href="#OTHERLIB">Other libraries</a></dt> +<dt>16. <a href="#PANELS">Panel Library</a></dt> +<dd> +<dl> +<dt>16.1. <a href="#PANELBASICS">The Basics</a></dt> +<dt>16.2. <a href="#COMPILEPANELS">Compiling With the Panels +Library</a></dt> +<dt>16.3. <a href="#PANELBROWSING">Panel Window Browsing</a></dt> +<dt>16.4. <a href="#USERPTRUSING">Using User Pointers</a></dt> +<dt>16.5. <a href="#PANELMOVERESIZE">Moving and Resizing +Panels</a></dt> +<dt>16.6. <a href="#PANELSHOWHIDE">Hiding and Showing +Panels</a></dt> +<dt>16.7. <a href="#PANELABOVE">panel_above() and panel_below() +Functions</a></dt> +</dl> +</dd> +<dt>17. <a href="#MENUS">Menus Library</a></dt> +<dd> +<dl> +<dt>17.1. <a href="#MENUBASICS">The Basics</a></dt> +<dt>17.2. <a href="#COMPILEMENUS">Compiling With the Menu +Library</a></dt> +<dt>17.3. <a href="#MENUDRIVER">Menu Driver: The work horse of the +menu system</a></dt> +<dt>17.4. <a href="#MENUWINDOWS">Menu Windows</a></dt> +<dt>17.5. <a href="#SCROLLMENUS">Scrolling Menus</a></dt> +<dt>17.6. <a href="#MULTICOLUMN">Multi Columnar Menus</a></dt> +<dt>17.7. <a href="#MULTIVALUEMENUS">Multi Valued Menus</a></dt> +<dt>17.8. <a href="#MENUOPT">Menu Options</a></dt> +<dt>17.9. <a href="#MENUUSERPTR">The useful User Pointer</a></dt> +</dl> +</dd> +<dt>18. <a href="#FORMS">Forms Library</a></dt> +<dd> +<dl> +<dt>18.1. <a href="#FORMBASICS">The Basics</a></dt> +<dt>18.2. <a href="#COMPILEFORMS">Compiling With the Forms +Library</a></dt> +<dt>18.3. <a href="#PLAYFIELDS">Playing with Fields</a></dt> +<dt>18.4. <a href="#FORMWINDOWS">Form Windows</a></dt> +<dt>18.5. <a href="#FILEDVALIDATE">Field Validation</a></dt> +<dt>18.6. <a href="#FORMDRIVER">Form Driver: The work horse of the +forms system</a></dt> +</dl> +</dd> +<dt>19. <a href="#TOOLS">Tools and Widget Libraries</a></dt> +<dd> +<dl> +<dt>19.1. <a href="#CDK">CDK (Curses Development Kit)</a></dt> +<dt>19.2. <a href="#DIALOG">The dialog</a></dt> +<dt>19.3. <a href="#PERLCURSES">Perl Curses Modules CURSES::FORM +and CURSES::WIDGETS</a></dt> +</dl> +</dd> +<dt>20. <a href="#JUSTFORFUN">Just For Fun !!!</a></dt> +<dd> +<dl> +<dt>20.1. <a href="#GAMEOFLIFE">The Game of Life</a></dt> +<dt>20.2. <a href="#MAGIC">Magic Square</a></dt> +<dt>20.3. <a href="#HANOI">Towers of Hanoi</a></dt> +<dt>20.4. <a href="#QUEENS">Queens Puzzle</a></dt> +<dt>20.5. <a href="#SHUFFLE">Shuffle</a></dt> +<dt>20.6. <a href="#TT">Typing Tutor</a></dt> +</dl> +</dd> +<dt>21. <a href="#REF">References</a></dt> +</dl> +</div> +<div class="SECT1"> +<h2 class="SECT1"><a name="INTRO" id="INTRO">1. +Introduction</a></h2> +<p>In the olden days of teletype terminals, terminals were away +from computers and were connected to them through serial cables. +The terminals could be configured by sending a series of bytes. All +the capabilities (such as moving the cursor to a new location, +erasing part of the screen, scrolling the screen, changing modes +etc.) of terminals could be accessed through these series of bytes. +These control seeuqnces are usually called escape sequences, +because they start with an escape(0x1B) character. Even today, with +proper emulation, we can send escape sequences to the emulator and +achieve the same effect on a terminal window.</p> +<p>Suppose you wanted to print a line in color. Try typing this on +your console.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000">echo "^[[0;31;40mIn Color"</font> +</pre></td> +</tr> +</table> +<p>The first character is an escape character, which looks like two +characters ^ and [. To be able to print it, you have to press +CTRL+V and then the ESC key. All the others are normal printable +characters. You should be able to see the string "In Color" in red. +It stays that way and to revert back to the original mode type +this.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000">echo "^[[0;37;40m"</font> +</pre></td> +</tr> +</table> +<p>Now, what do these magic characters mean? Difficult to +comprehend? They might even be different for different terminals. +So the designers of UNIX invented a mechanism named <var class= +"LITERAL">termcap</var>. It is a file that lists all the +capabilities of a particular terminal, along with the escape +sequences needed to achieve a particular effect. In the later +years, this was replaced by <var class="LITERAL">terminfo</var>. +Without delving too much into details, this mechanism allows +application programs to query the terminfo database and obtain the +control characters to be sent to a terminal or terminal +emulator.</p> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="WHATIS" id="WHATIS">1.1. What is +NCURSES?</a></h3> +<p>You might be wondering, what the import of all this technical +gibberish is. In the above scenario, every application program is +supposed to query the terminfo and perform the necessary stuff +(sending control characters etc.). It soon became difficult to +manage this complexity and this gave birth to 'CURSES'. Curses is a +pun on the name "cursor optimization". The Curses library forms a +wrapper over working with raw terminal codes, and provides highly +flexible and efficient API (Application Programming Interface). It +provides functions to move the cursor, create windows, produce +colors, play with mouse etc. The application programs need not +worry about the underlying terminal capabilities.</p> +<p>So what is NCURSES? NCURSES is a clone of the original System V +Release 4.0 (SVr4) curses. It is a freely distributable library, +fully compatible with older version of curses. In short, it is a +library of functions that manages an application's display on +character-cell terminals. In the remainder of the document, the +terms curses and ncurses are used interchangeably.</p> +<p>A detailed history of NCURSES can be found in the NEWS file from +the source distribution. The current package is maintained by +<a href="mailto:dickey@his.com" target="_top">Thomas Dickey</a>. +You can contact the maintainers at <a href= +"mailto:bug-ncurses@gnu.org" target= +"_top">bug-ncurses@gnu.org</a>.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="WHATCANWEDO" id="WHATCANWEDO">1.2. What +we can do with NCURSES</a></h3> +<p>NCURSES not only creates a wrapper over terminal capabilities, +but also gives a robust framework to create nice looking UI (User +Interface)s in text mode. It provides functions to create windows +etc. Its sister libraries panel, menu and form provide an extension +to the basic curses library. These libraries usually come along +with curses. One can create applications that contain multiple +windows, menus, panels and forms. Windows can be managed +independently, can provide 'scrollability' and even can be +hidden.</p> +<p>Menus provide the user with an easy command selection option. +Forms allow the creation of easy-to-use data entry and display +windows. Panels extend the capabilities of ncurses to deal with +overlapping and stacked windows.</p> +<p>These are just some of the basic things we can do with ncurses. +As we move along, We will see all the capabilities of these +libraries.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="WHERETOGETIT" id="WHERETOGETIT">1.3. +Where to get it</a></h3> +<p>All right, now that you know what you can do with ncurses, you +must be rearing to get started. NCURSES is usually shipped with +your installation. In case you don't have the library or want to +compile it on your own, read on.</p> +<p><em>Compiling the package</em></p> +<p>NCURSES can be obtained from <a href= +"ftp://ftp.gnu.org/pub/gnu/ncurses/ncurses.tar.gz" target= +"_top">ftp://ftp.gnu.org/pub/gnu/ncurses/ncurses.tar.gz</a> or any +of the ftp sites mentioned in <a href= +"http://www.gnu.org/order/ftp.html" target= +"_top">http://www.gnu.org/order/ftp.html</a>.</p> +<p>Read the README and INSTALL files for details on to how to +install it. It usually involves the following operations.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000"> tar zxvf ncurses<version>.tar.gz # unzip and untar the archive + cd ncurses<version> # cd to the directory + ./configure # configure the build according to your + # environment + make # make it + su root # become root + make install # install it</font> +</pre></td> +</tr> +</table> +<p><em>Using the RPM</em></p> +<p>NCURSES RPM can be found and downloaded from <a href= +"http://rpmfind.net" target="_top">http://rpmfind.net</a> . The RPM +can be installed with the following command after becoming +root.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> rpm -i <downloaded rpm></font> +</pre></td> +</tr> +</table> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="PURPOSE" id="PURPOSE">1.4. Purpose/Scope +of the document</a></h3> +<p>This document is intended to be a "All in One" guide for +programming with ncurses and its sister libraries. We graduate from +a simple "Hello World" program to more complex form manipulation. +No prior experience in ncurses is assumed. The writing is informal, +but a lot of detail is provided for each of the examples.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="ABOUTPROGRAMS" id="ABOUTPROGRAMS">1.5. +About the Programs</a></h3> +<p>All the programs in the document are available in zipped form +<a href= +"http://www.tldp.org/HOWTO/NCURSES-Programming-HOWTO/ncurses_programs.tar.gz" +target="_top">here</a>. Unzip and untar it. The directory structure +looks like this.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000">ncurses + | + |----> JustForFun -- just for fun programs + |----> basics -- basic programs + |----> demo -- output files go into this directory after make + | | + | |----> exe -- exe files of all example programs + |----> forms -- programs related to form library + |----> menus -- programs related to menus library + |----> panels -- programs related to panels library + |----> perl -- perl equivalents of the examples (contributed + | by Anuradha Ratnaweera) + |----> Makefile -- the top level Makefile + |----> README -- the top level README file. contains instructions + |----> COPYING -- copyright notice</font> +</pre></td> +</tr> +</table> +<p>The individual directories contain the following files.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000">Description of files in each directory +-------------------------------------- +JustForFun + | + |----> hanoi.c -- The Towers of Hanoi Solver + |----> life.c -- The Game of Life demo + |----> magic.c -- An Odd Order Magic Square builder + |----> queens.c -- The famous N-Queens Solver + |----> shuffle.c -- A fun game, if you have time to kill + |----> tt.c -- A very trivial typing tutor + + basics + | + |----> acs_vars.c -- ACS_ variables example + |----> hello_world.c -- Simple "Hello World" Program + |----> init_func_example.c -- Initialization functions example + |----> key_code.c -- Shows the scan code of the key pressed + |----> mouse_menu.c -- A menu accessible by mouse + |----> other_border.c -- Shows usage of other border functions apa + | -- rt from box() + |----> printw_example.c -- A very simple printw() example + |----> scanw_example.c -- A very simple getstr() example + |----> simple_attr.c -- A program that can print a c file with + | -- comments in attribute + |----> simple_color.c -- A simple example demonstrating colors + |----> simple_key.c -- A menu accessible with keyboard UP, DOWN + | -- arrows + |----> temp_leave.c -- Demonstrates temporarily leaving curses mode + |----> win_border.c -- Shows Creation of windows and borders + |----> with_chgat.c -- chgat() usage example + + forms + | + |----> form_attrib.c -- Usage of field attributes + |----> form_options.c -- Usage of field options + |----> form_simple.c -- A simple form example + |----> form_win.c -- Demo of windows associated with forms + + menus + | + |----> menu_attrib.c -- Usage of menu attributes + |----> menu_item_data.c -- Usage of item_name() etc.. functions + |----> menu_multi_column.c -- Creates multi columnar menus + |----> menu_scroll.c -- Demonstrates scrolling capability of menus + |----> menu_simple.c -- A simple menu accessed by arrow keys + |----> menu_toggle.c -- Creates multi valued menus and explains + | -- REQ_TOGGLE_ITEM + |----> menu_userptr.c -- Usage of user pointer + |----> menu_win.c -- Demo of windows associated with menus + + panels + | + |----> panel_browse.c -- Panel browsing through tab. Usage of user + | -- pointer + |----> panel_hide.c -- Hiding and Un hiding of panels + |----> panel_resize.c -- Moving and resizing of panels + |----> panel_simple.c -- A simple panel example + + perl + |----> 01-10.pl -- Perl equivalents of first ten example programs</font> +</pre></td> +</tr> +</table> +<p>There is a top level Makefile included in the main directory. It +builds all the files and puts the ready-to-use exes in demo/exe +directory. You can also do selective make by going into the +corresponding directory. Each directory contains a README file +explaining the purpose of each c file in the directory.</p> +<p>For every example, I have included path name for the file +relative to the examples directory.</p> +<p>If you prefer browsing individual programs, point your browser +to <a href= +"http://tldp.org/HOWTO/NCURSES-Programming-HOWTO/ncurses_programs/" +target= +"_top">http://tldp.org/HOWTO/NCURSES-Programming-HOWTO/ncurses_programs/</a></p> +<p>All the programs are released under the same license that is +used by ncurses (MIT-style). This gives you the ability to do +pretty much anything other than claiming them as yours. Feel free +to use them in your programs as appropriate.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="OTHERFORMATS" id="OTHERFORMATS">1.6. +Other Formats of the document</a></h3> +<p>This howto is also availabe in various other formats on the +tldp.org site. Here are the links to other formats of this +document.</p> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="LISTFORMATS" id="LISTFORMATS">1.6.1. +Readily available formats from tldp.org</a></h4> +<ul> +<li> +<p><a href= +"http://www.ibiblio.org/pub/Linux/docs/HOWTO/other-formats/pdf/NCURSES-Programming-HOWTO.pdf" +target="_top">Acrobat PDF Format</a></p> +</li> +<li> +<p><a href= +"http://www.ibiblio.org/pub/Linux/docs/HOWTO/other-formats/ps/NCURSES-Programming-HOWTO.ps.gz" +target="_top">PostScript Format</a></p> +</li> +<li> +<p><a href= +"http://www.ibiblio.org/pub/Linux/docs/HOWTO/other-formats/html/NCURSES-Programming-HOWTO-html.tar.gz" +target="_top">In Multiple HTML pages</a></p> +</li> +<li> +<p><a href= +"http://www.ibiblio.org/pub/Linux/docs/HOWTO/other-formats/html_single/NCURSES-Programming-HOWTO.html" +target="_top">In One big HTML format</a></p> +</li> +</ul> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="BUILDSOURCE" id="BUILDSOURCE">1.6.2. +Building from source</a></h4> +<p>If above links are broken or if you want to experiment with sgml +read on.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000"> Get both the source and the tar,gzipped programs, available at + http://cvsview.tldp.org/index.cgi/LDP/howto/docbook/ + NCURSES-HOWTO/NCURSES-Programming-HOWTO.sgml + http://cvsview.tldp.org/index.cgi/LDP/howto/docbook/ + NCURSES-HOWTO/ncurses_programs.tar.gz + + Unzip ncurses_programs.tar.gz with + tar zxvf ncurses_programs.tar.gz + + Use jade to create various formats. For example if you just want to create + the multiple html files, you would use + jade -t sgml -i html -d <path to docbook html stylesheet> + NCURSES-Programming-HOWTO.sgml + to get pdf, first create a single html file of the HOWTO with + jade -t sgml -i html -d <path to docbook html stylesheet> -V nochunks + NCURSES-Programming-HOWTO.sgml > NCURSES-ONE-BIG-FILE.html + then use htmldoc to get pdf file with + htmldoc --size universal -t pdf --firstpage p1 -f <output file name.pdf> + NCURSES-ONE-BIG-FILE.html + for ps, you would use + htmldoc --size universal -t ps --firstpage p1 -f <output file name.ps> + NCURSES-ONE-BIG-FILE.html</font> +</pre></td> +</tr> +</table> +<p>See <a href="http://www.tldp.org/LDP/LDP-Author-Guide/" target= +"_top">LDP Author guide</a> for more details. If all else failes, +mail me at <a href="ppadala@gmail.com" target= +"_top">ppadala@gmail.com</a></p> +</div> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="CREDITS" id="CREDITS">1.7. +Credits</a></h3> +<p>I thank <a href="mailto:sharath_1@usa.net" target= +"_top">Sharath</a> and Emre Akbas for helping me with few sections. +The introduction was initially written by sharath. I rewrote it +with few excerpts taken from his initial work. Emre helped in +writing printw and scanw sections.</p> +<p>Perl equivalents of the example programs are contributed by +<a href="mailto:Aratnaweera@virtusa.com" target="_top">Anuradha +Ratnaweera</a>.</p> +<p>Then comes <a href="mailto:parimi@ece.arizona.edu" target= +"_top">Ravi Parimi</a>, my dearest friend, who has been on this +project before even one line was written. He constantly bombarded +me with suggestions and patiently reviewed the whole text. He also +checked each program on Linux and Solaris.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="WISHLIST" id="WISHLIST">1.8. Wish +List</a></h3> +<p>This is the wish list, in the order of priority. If you have a +wish or you want to work on completing the wish, mail <a href= +"mailto:ppadala@gmail.com" target="_top">me</a>.</p> +<ul> +<li> +<p>Add examples to last parts of forms section.</p> +</li> +<li> +<p>Prepare a Demo showing all the programs and allow the user to +browse through description of each program. Let the user compile +and see the program in action. A dialog based interface is +preferred.</p> +</li> +<li> +<p>Add debug info. _tracef, _tracemouse stuff.</p> +</li> +<li> +<p>Accessing termcap, terminfo using functions provided by ncurses +package.</p> +</li> +<li> +<p>Working on two terminals simultaneously.</p> +</li> +<li> +<p>Add more stuff to miscellaneous section.</p> +</li> +</ul> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="COPYRIGHT" id="COPYRIGHT">1.9. +Copyright</a></h3> +<p>Copyright © 2001 by Pradeep Padala.</p> +<p>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:</p> +<p>The above copyright notice and this permission notice shall be +included in all copies or substantial portions of the Software.</p> +<p>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.</p> +<p>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.</p> +</div> +</div> +<div class="SECT1"> +<hr> +<h2 class="SECT1"><a name="HELLOWORLD" id="HELLOWORLD">2. Hello +World !!!</a></h2> +<p>Welcome to the world of curses. Before we plunge into the +library and look into its various features, let's write a simple +program and say hello to the world.</p> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="COMPILECURSES" id="COMPILECURSES">2.1. +Compiling With the NCURSES Library</a></h3> +<p>To use ncurses library functions, you have to include ncurses.h +in your programs. To link the program with ncurses the flag +-lncurses should be added.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> #include <ncurses.h> + . + . + . + + compile and link: gcc <program file> -lncurses</font> +</pre></td> +</tr> +</table> +<div class="EXAMPLE"><a name="BHW" id="BHW"></a> +<p><b>Example 1. The Hello World !!! Program</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <ncurses.h> + +int main() +{ + initscr(); /* Start curses mode */ + printw("Hello World !!!"); /* Print Hello World */ + refresh(); /* Print it on to the real screen */ + getch(); /* Wait for user input */ + endwin(); /* End curses mode */ + + return 0; +}</span></font> +</pre></td> +</tr> +</table> +</div> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="DISSECTION" id="DISSECTION">2.2. +Dissection</a></h3> +<p>The above program prints "Hello World !!!" to the screen and +exits. This program shows how to initialize curses and do screen +manipulation and end curses mode. Let's dissect it line by +line.</p> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="ABOUT-INITSCR" id="ABOUT-INITSCR">2.2.1. +About initscr()</a></h4> +<p>The function initscr() initializes the terminal in curses mode. +In some implementations, it clears the screen and presents a blank +screen. To do any screen manipulation using curses package this has +to be called first. This function initializes the curses system and +allocates memory for our present window (called <var class= +"LITERAL">stdscr</var>) and some other data-structures. Under +extreme cases this function might fail due to insufficient memory +to allocate memory for curses library's data structures.</p> +<p>After this is done, we can do a variety of initializations to +customize our curses settings. These details will be explained +<a href="#INIT">later</a> .</p> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="MYST-REFRESH" id="MYST-REFRESH">2.2.2. +The mysterious refresh()</a></h4> +<p>The next line printw prints the string "Hello World !!!" on to +the screen. This function is analogous to normal printf in all +respects except that it prints the data on a window called stdscr +at the current (y,x) co-ordinates. Since our present co-ordinates +are at 0,0 the string is printed at the left hand corner of the +window.</p> +<p>This brings us to that mysterious refresh(). Well, when we +called printw the data is actually written to an imaginary window, +which is not updated on the screen yet. The job of printw is to +update a few flags and data structures and write the data to a +buffer corresponding to stdscr. In order to show it on the screen, +we need to call refresh() and tell the curses system to dump the +contents on the screen.</p> +<p>The philosophy behind all this is to allow the programmer to do +multiple updates on the imaginary screen or windows and do a +refresh once all his screen update is done. refresh() checks the +window and updates only the portion which has been changed. This +improves performance and offers greater flexibility too. But, it is +sometimes frustrating to beginners. A common mistake committed by +beginners is to forget to call refresh() after they did some update +through printw() class of functions. I still forget to add it +sometimes :-)</p> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="ABOUT-ENDWIN" id="ABOUT-ENDWIN">2.2.3. +About endwin()</a></h4> +<p>And finally don't forget to end the curses mode. Otherwise your +terminal might behave strangely after the program quits. endwin() +frees the memory taken by curses sub-system and its data structures +and puts the terminal in normal mode. This function must be called +after you are done with the curses mode.</p> +</div> +</div> +</div> +<div class="SECT1"> +<hr> +<h2 class="SECT1"><a name="GORY" id="GORY">3. The Gory +Details</a></h2> +<p>Now that we have seen how to write a simple curses program let's +get into the details. There are many functions that help customize +what you see on screen and many features which can be put to full +use.</p> +<p>Here we go...</p> +</div> +<div class="SECT1"> +<hr> +<h2 class="SECT1"><a name="INIT" id="INIT">4. +Initialization</a></h2> +<p>We now know that to initialize curses system the function +initscr() has to be called. There are functions which can be called +after this initialization to customize our curses session. We may +ask the curses system to set the terminal in raw mode or initialize +color or initialize the mouse etc.. Let's discuss some of the +functions that are normally called immediately after initscr();</p> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="ABOUTINIT" id="ABOUTINIT">4.1. +Initialization functions</a></h3> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="RAWCBREAK" id="RAWCBREAK">4.2. raw() and +cbreak()</a></h3> +<p>Normally the terminal driver buffers the characters a user types +until a new line or carriage return is encountered. But most +programs require that the characters be available as soon as the +user types them. The above two functions are used to disable line +buffering. The difference between these two functions is in the way +control characters like suspend (CTRL-Z), interrupt and quit +(CTRL-C) are passed to the program. In the raw() mode these +characters are directly passed to the program without generating a +signal. In the <var class="LITERAL">cbreak()</var> mode these +control characters are interpreted as any other character by the +terminal driver. I personally prefer to use raw() as I can exercise +greater control over what the user does.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="ECHONOECHO" id="ECHONOECHO">4.3. echo() +and noecho()</a></h3> +<p>These functions control the echoing of characters typed by the +user to the terminal. <var class="LITERAL">noecho()</var> switches +off echoing. The reason you might want to do this is to gain more +control over echoing or to suppress unnecessary echoing while +taking input from the user through the getch() etc. functions. Most +of the interactive programs call <var class= +"LITERAL">noecho()</var> at initialization and do the echoing of +characters in a controlled manner. It gives the programmer the +flexibility of echoing characters at any place in the window +without updating current (y,x) co-ordinates.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="KEYPAD" id="KEYPAD">4.4. +keypad()</a></h3> +<p>This is my favorite initialization function. It enables the +reading of function keys like F1, F2, arrow keys etc. Almost every +interactive program enables this, as arrow keys are a major part of +any User Interface. Do <var class="LITERAL">keypad(stdscr, +TRUE)</var> to enable this feature for the regular screen (stdscr). +You will learn more about key management in later sections of this +document.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="HALFDELAY" id="HALFDELAY">4.5. +halfdelay()</a></h3> +<p>This function, though not used very often, is a useful one at +times. halfdelay()is called to enable the half-delay mode, which is +similar to the cbreak() mode in that characters typed are +immediately available to program. However, it waits for 'X' tenths +of a second for input and then returns ERR, if no input is +available. 'X' is the timeout value passed to the function +halfdelay(). This function is useful when you want to ask the user +for input, and if he doesn't respond with in certain time, we can +do some thing else. One possible example is a timeout at the +password prompt.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="MISCINIT" id="MISCINIT">4.6. +Miscellaneous Initialization functions</a></h3> +<p>There are few more functions which are called at initialization +to customize curses behavior. They are not used as extensively as +those mentioned above. Some of them are explained where +appropriate.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="INITEX" id="INITEX">4.7. An +Example</a></h3> +<p>Let's write a program which will clarify the usage of these +functions.</p> +<div class="EXAMPLE"><a name="BINFU" id="BINFU"></a> +<p><b>Example 2. Initialization Function Usage example</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <ncurses.h> + +int main() +{ int ch; + + initscr(); /* Start curses mode */ + raw(); /* Line buffering disabled */ + keypad(stdscr, TRUE); /* We get F1, F2 etc.. */ + noecho(); /* Don't echo() while we do getch */ + + printw("Type any character to see it in bold\n"); + ch = getch(); /* If raw() hadn't been called + * we have to press enter before it + * gets to the program */ + if(ch == KEY_F(1)) /* Without keypad enabled this will */ + printw("F1 Key pressed");/* not get to us either */ + /* Without noecho() some ugly escape + * charachters might have been printed + * on screen */ + else + { printw("The pressed key is "); + attron(A_BOLD); + printw("%c", ch); + attroff(A_BOLD); + } + refresh(); /* Print it on to the real screen */ + getch(); /* Wait for user input */ + endwin(); /* End curses mode */ + + return 0; +}</span></font> +</pre></td> +</tr> +</table> +</div> +<p>This program is self-explanatory. But I used functions which +aren't explained yet. The function <var class= +"LITERAL">getch()</var> is used to get a character from user. It is +equivalent to normal <var class="LITERAL">getchar()</var> except +that we can disable the line buffering to avoid <enter> after +input. Look for more about <var class="LITERAL">getch()</var>and +reading keys in the <a href="#KEYS">key management section</a> . +The functions attron and attroff are used to switch some attributes +on and off respectively. In the example I used them to print the +character in bold. These functions are explained in detail +later.</p> +</div> +</div> +<div class="SECT1"> +<hr> +<h2 class="SECT1"><a name="AWORDWINDOWS" id="AWORDWINDOWS">5. A +Word about Windows</a></h2> +<p>Before we plunge into the myriad ncurses functions, let me clear +few things about windows. Windows are explained in detail in +following <a href="#WINDOWS">sections</a></p> +<p>A Window is an imaginary screen defined by curses system. A +window does not mean a bordered window which you usually see on +Win9X platforms. When curses is initialized, it creates a default +window named <var class="LITERAL">stdscr</var> which represents +your 80x25 (or the size of window in which you are running) screen. +If you are doing simple tasks like printing few strings, reading +input etc., you can safely use this single window for all of your +purposes. You can also create windows and call functions which +explicitly work on the specified window.</p> +<p>For example, if you call</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> printw("Hi There !!!"); + refresh();</font> +</pre></td> +</tr> +</table> +<p>It prints the string on stdscr at the present cursor position. +Similarly the call to refresh(), works on stdscr only.</p> +<p>Say you have created <a href="#WINDOWS">windows</a> then you +have to call a function with a 'w' added to the usual function.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> wprintw(win, "Hi There !!!"); + wrefresh(win);</font> +</pre></td> +</tr> +</table> +<p>As you will see in the rest of the document, naming of functions +follow the same convention. For each function there usually are +three more functions.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000"> printw(string); /* Print on stdscr at present cursor position */ + mvprintw(y, x, string);/* Move to (y, x) then print string */ + wprintw(win, string); /* Print on window win at present cursor position */ + /* in the window */ + mvwprintw(win, y, x, string); /* Move to (y, x) relative to window */ + /* co-ordinates and then print */</font> +</pre></td> +</tr> +</table> +<p>Usually the w-less functions are macros which expand to +corresponding w-function with stdscr as the window parameter.</p> +</div> +<div class="SECT1"> +<hr> +<h2 class="SECT1"><a name="PRINTW" id="PRINTW">6. Output +functions</a></h2> +<p>I guess you can't wait any more to see some action. Back to our +odyssey of curses functions. Now that curses is initialized, let's +interact with world.</p> +<p>There are three classes of functions which you can use to do +output on screen.</p> +<ol type="1"> +<li> +<p>addch() class: Print single character with attributes</p> +</li> +<li> +<p>printw() class: Print formatted output similar to printf()</p> +</li> +<li> +<p>addstr() class: Print strings</p> +</li> +</ol> +<p>These functions can be used interchangeably and it's a matter of +style as to which class is used. Let's see each one in detail.</p> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="ADDCHCLASS" id="ADDCHCLASS">6.1. addch() +class of functions</a></h3> +<p>These functions put a single character into the current cursor +location and advance the position of the cursor. You can give the +character to be printed but they usually are used to print a +character with some attributes. Attributes are explained in detail +in later <a href="#ATTRIB">sections</a> of the document. If a +character is associated with an attribute(bold, reverse video +etc.), when curses prints the character, it is printed in that +attribute.</p> +<p>In order to combine a character with some attributes, you have +two options:</p> +<ul> +<li> +<p>By OR'ing a single character with the desired attribute macros. +These attribute macros could be found in the header file +<var class="LITERAL">ncurses.h</var>. For example, you want to +print a character ch(of type char) bold and underlined, you would +call addch() as below.</p> +<table border="0" bgcolor="#E0E0E0" width="90%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> addch(ch | A_BOLD | A_UNDERLINE);</font> +</pre></td> +</tr> +</table> +</li> +<li> +<p>By using functions like <var class= +"LITERAL">attrset(),attron(),attroff()</var>. These functions are +explained in the <a href="#ATTRIB">Attributes</a> section. Briefly, +they manipulate the current attributes of the given window. Once +set, the character printed in the window are associated with the +attributes until it is turned off.</p> +</li> +</ul> +<p>Additionally, <var class="LITERAL">curses</var> provides some +special characters for character-based graphics. You can draw +tables, horizontal or vertical lines, etc. You can find all +avaliable characters in the header file <var class= +"LITERAL">ncurses.h</var>. Try looking for macros beginning with +<var class="LITERAL">ACS_</var> in this file.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="AEN298" id="AEN298">6.2. mvaddch(), +waddch() and mvwaddch()</a></h3> +<p><var class="LITERAL">mvaddch()</var> is used to move the cursor +to a given point, and then print. Thus, the calls:</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000"> move(row,col); /* moves the cursor to row<em>th</em> row and col<em>th</em> column */ + addch(ch);</font> +</pre></td> +</tr> +</table> +can be replaced by +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> mvaddch(row,col,ch);</font> +</pre></td> +</tr> +</table> +<p><var class="LITERAL">waddch()</var> is similar to <var class= +"LITERAL">addch()</var>, except that it adds a character into the +given window. (Note that <var class="LITERAL">addch()</var> adds a +character into the window <var class="LITERAL">stdscr</var>.)</p> +<p>In a similar fashion <var class="LITERAL">mvwaddch()</var> +function is used to add a character into the given window at the +given coordinates.</p> +<p>Now, we are familiar with the basic output function <var class= +"LITERAL">addch()</var>. But, if we want to print a string, it +would be very annoying to print it character by character. +Fortunately, <var class="LITERAL">ncurses</var> provides +<var class="LITERAL">printf</var><em>-like</em> or <var class= +"LITERAL">puts</var><em>-like</em> functions.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="PRINTWCLASS" id="PRINTWCLASS">6.3. +printw() class of functions</a></h3> +<p>These functions are similar to <var class= +"LITERAL">printf()</var> with the added capability of printing at +any position on the screen.</p> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="PRINTWMVPRINTW" id= +"PRINTWMVPRINTW">6.3.1. printw() and mvprintw</a></h4> +<p>These two functions work much like <var class= +"LITERAL">printf()</var>. <var class="LITERAL">mvprintw()</var> can +be used to move the cursor to a position and then print. If you +want to move the cursor first and then print using <var class= +"LITERAL">printw()</var> function, use <var class= +"LITERAL">move()</var> first and then use <var class= +"LITERAL">printw()</var> though I see no point why one should avoid +using <var class="LITERAL">mvprintw()</var>, you have the +flexibility to manipulate.</p> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="WPRINTWMVWPRINTW" id= +"WPRINTWMVWPRINTW">6.3.2. wprintw() and mvwprintw</a></h4> +<p>These two functions are similar to above two except that they +print in the corresponding window given as argument.</p> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="VWPRINTW" id="VWPRINTW">6.3.3. +vwprintw()</a></h4> +<p>This function is similar to <var class= +"LITERAL">vprintf()</var>. This can be used when variable number of +arguments are to be printed.</p> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="SIMPLEPRINTWEX" id= +"SIMPLEPRINTWEX">6.3.4. A Simple printw example</a></h4> +<div class="EXAMPLE"><a name="BPREX" id="BPREX"></a> +<p><b>Example 3. A Simple printw example</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <ncurses.h> /* ncurses.h includes stdio.h */ +#include <string.h> + +int main() +{ + char mesg[]="Just a string"; /* message to be appeared on the screen */ + int row,col; /* to store the number of rows and * + * the number of colums of the screen */ + initscr(); /* start the curses mode */ + getmaxyx(stdscr,row,col); /* get the number of rows and columns */ + mvprintw(row/2,(col-strlen(mesg))/2,"%s",mesg); + /* print the message at the center of the screen */ + mvprintw(row-2,0,"This screen has %d rows and %d columns\n",row,col); + printw("Try resizing your window(if possible) and then run this program again"); + refresh(); + getch(); + endwin(); + + return 0; +}</span></font> +</pre></td> +</tr> +</table> +</div> +<p>Above program demonstrates how easy it is to use <var class= +"LITERAL">printw</var>. You just feed the coordinates and the +message to be appeared on the screen, then it does what you +want.</p> +<p>The above program introduces us to a new function <var class= +"LITERAL">getmaxyx()</var>, a macro defined in <var class= +"LITERAL">ncurses.h</var>. It gives the number of columns and the +number of rows in a given window. <var class= +"LITERAL">getmaxyx()</var> does this by updating the variables +given to it. Since <var class="LITERAL">getmaxyx()</var> is not a +function we don't pass pointers to it, we just give two integer +variables.</p> +</div> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="ADDSTRCLASS" id="ADDSTRCLASS">6.4. +addstr() class of functions</a></h3> +<p><var class="LITERAL">addstr()</var> is used to put a character +string into a given window. This function is similar to calling +<var class="LITERAL">addch()</var> once for each character in a +given string. This is true for all output functions. There are +other functions from this family such as <var class= +"LITERAL">mvaddstr(),mvwaddstr()</var> and <var class= +"LITERAL">waddstr()</var>, which obey the naming convention of +curses.(e.g. mvaddstr() is similar to the respective calls move() +and then addstr().) Another function of this family is addnstr(), +which takes an integer parameter(say n) additionally. This function +puts at most n characters into the screen. If n is negative, then +the entire string will be added.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="ACAUTION" id="ACAUTION">6.5. A word of +caution</a></h3> +<p>All these functions take y co-ordinate first and then x in their +arguments. A common mistake by beginners is to pass x,y in that +order. If you are doing too many manipulations of (y,x) +co-ordinates, think of dividing the screen into windows and +manipulate each one separately. Windows are explained in the +<a href="#WINDOWS">windows</a> section.</p> +</div> +</div> +<div class="SECT1"> +<hr> +<h2 class="SECT1"><a name="SCANW" id="SCANW">7. Input +functions</a></h2> +<p>Well, printing without taking input, is boring. Let's see +functions which allow us to get input from user. These functions +also can be divided into three categories.</p> +<ol type="1"> +<li> +<p>getch() class: Get a character</p> +</li> +<li> +<p>scanw() class: Get formatted input</p> +</li> +<li> +<p>getstr() class: Get strings</p> +</li> +</ol> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="GETCHCLASS" id="GETCHCLASS">7.1. getch() +class of functions</a></h3> +<p>These functions read a single character from the terminal. But +there are several subtle facts to consider. For example if you +don't use the function cbreak(), curses will not read your input +characters contiguously but will begin read them only after a new +line or an EOF is encountered. In order to avoid this, the cbreak() +function must used so that characters are immediately available to +your program. Another widely used function is noecho(). As the name +suggests, when this function is set (used), the characters that are +keyed in by the user will not show up on the screen. The two +functions cbreak() and noecho() are typical examples of key +management. Functions of this genre are explained in the <a href= +"#KEYS">key management section</a> .</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="SCANWCLASS" id="SCANWCLASS">7.2. scanw() +class of functions</a></h3> +<p>These functions are similar to <var class= +"LITERAL">scanf()</var> with the added capability of getting the +input from any location on the screen.</p> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="SCANWMVSCANW" id="SCANWMVSCANW">7.2.1. +scanw() and mvscanw</a></h4> +<p>The usage of these functions is similar to that of <var class= +"LITERAL">sscanf()</var>, where the line to be scanned is provided +by <var class="LITERAL">wgetstr()</var> function. That is, these +functions call to <var class="LITERAL">wgetstr()</var> +function(explained below) and uses the resulting line for a +scan.</p> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="WSCANWMVWSCANW" id= +"WSCANWMVWSCANW">7.2.2. wscanw() and mvwscanw()</a></h4> +<p>These are similar to above two functions except that they read +from a window, which is supplied as one of the arguments to these +functions.</p> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="VWSCANW" id="VWSCANW">7.2.3. +vwscanw()</a></h4> +<p>This function is similar to <var class="LITERAL">vscanf()</var>. +This can be used when a variable number of arguments are to be +scanned.</p> +</div> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="GETSTRCLASS" id="GETSTRCLASS">7.3. +getstr() class of functions</a></h3> +<p>These functions are used to get strings from the terminal. In +essence, this function performs the same task as would be achieved +by a series of calls to <var class="LITERAL">getch()</var> until a +newline, carriage return, or end-of-file is received. The resulting +string of characters are pointed to by <var class= +"LITERAL">str</var>, which is a character pointer provided by the +user.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="GETSTREX" id="GETSTREX">7.4. Some +examples</a></h3> +<div class="EXAMPLE"><a name="BSCEX" id="BSCEX"></a> +<p><b>Example 4. A Simple scanw example</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <ncurses.h> /* ncurses.h includes stdio.h */ +#include <string.h> + +int main() +{ + char mesg[]="Enter a string: "; /* message to be appeared on the screen */ + char str[80]; + int row,col; /* to store the number of rows and * + * the number of colums of the screen */ + initscr(); /* start the curses mode */ + getmaxyx(stdscr,row,col); /* get the number of rows and columns */ + mvprintw(row/2,(col-strlen(mesg))/2,"%s",mesg); + /* print the message at the center of the screen */ + getstr(str); + mvprintw(LINES - 2, 0, "You Entered: %s", str); + getch(); + endwin(); + + return 0; +}</span></font> +</pre></td> +</tr> +</table> +</div> +</div> +</div> +<div class="SECT1"> +<hr> +<h2 class="SECT1"><a name="ATTRIB" id="ATTRIB">8. +Attributes</a></h2> +<p>We have seen an example of how attributes can be used to print +characters with some special effects. Attributes, when set +prudently, can present information in an easy, understandable +manner. The following program takes a C file as input and prints +the file with comments in bold. Scan through the code.</p> +<div class="EXAMPLE"><a name="BSIAT" id="BSIAT"></a> +<p><b>Example 5. A Simple Attributes example</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">/* pager functionality by Joseph Spainhour" <spainhou@bellsouth.net> */ +#include <ncurses.h> +#include <stdlib.h> + +int main(int argc, char *argv[]) +{ + int ch, prev, row, col; + prev = EOF; + FILE *fp; + int y, x; + + if(argc != 2) + { + printf("Usage: %s <a c file name>\n", argv[0]); + exit(1); + } + fp = fopen(argv[1], "r"); + if(fp == NULL) + { + perror("Cannot open input file"); + exit(1); + } + initscr(); /* Start curses mode */ + getmaxyx(stdscr, row, col); /* find the boundaries of the screeen */ + while((ch = fgetc(fp)) != EOF) /* read the file till we reach the end */ + { + getyx(stdscr, y, x); /* get the current curser position */ + if(y == (row - 1)) /* are we are at the end of the screen */ + { + printw("<-Press Any Key->"); /* tell the user to press a key */ + getch(); + clear(); /* clear the screen */ + move(0, 0); /* start at the beginning of the screen */ + } + if(prev == '/' && ch == '*') /* If it is / and * then only + * switch bold on */ + { + attron(A_BOLD); /* cut bold on */ + getyx(stdscr, y, x); /* get the current curser position */ + move(y, x - 1); /* back up one space */ + printw("%c%c", '/', ch); /* The actual printing is done here */ + } + else + printw("%c", ch); + refresh(); + if(prev == '*' && ch == '/') + attroff(A_BOLD); /* Switch it off once we got * + * and then / */ + prev = ch; + } + endwin(); /* End curses mode */ + fclose(fp); + return 0; +}</span></font> +</pre></td> +</tr> +</table> +</div> +<p>Don't worry about all those initialization and other crap. +Concentrate on the while loop. It reads each character in the file +and searches for the pattern /*. Once it spots the pattern, it +switches the BOLD attribute on with <var class= +"LITERAL">attron()</var> . When we get the pattern */ it is +switched off by <var class="LITERAL">attroff()</var> .</p> +<p>The above program also introduces us to two useful functions +<var class="LITERAL">getyx()</var> and <var class= +"LITERAL">move()</var>. The first function gets the co-ordinates of +the present cursor into the variables y, x. Since getyx() is a +macro we don't have to pass pointers to variables. The function +<var class="LITERAL">move()</var> moves the cursor to the +co-ordinates given to it.</p> +<p>The above program is really a simple one which doesn't do much. +On these lines one could write a more useful program which reads a +C file, parses it and prints it in different colors. One could even +extend it to other languages as well.</p> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="ATTRIBDETAILS" id="ATTRIBDETAILS">8.1. +The details</a></h3> +<p>Let's get into more details of attributes. The functions +<var class="LITERAL">attron(), attroff(), attrset()</var> , and +their sister functions <var class="LITERAL">attr_get()</var> etc.. +can be used to switch attributes on/off , get attributes and +produce a colorful display.</p> +<p>The functions attron and attroff take a bit-mask of attributes +and switch them on or off, respectively. The following video +attributes, which are defined in <curses.h> can be passed to +these functions.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> + A_NORMAL Normal display (no highlight) + A_STANDOUT Best highlighting mode of the terminal. + A_UNDERLINE Underlining + A_REVERSE Reverse video + A_BLINK Blinking + A_DIM Half bright + A_BOLD Extra bright or bold + A_PROTECT Protected mode + A_INVIS Invisible or blank mode + A_ALTCHARSET Alternate character set + A_CHARTEXT Bit-mask to extract a character + COLOR_PAIR(n) Color-pair number n + </font> +</pre></td> +</tr> +</table> +<p>The last one is the most colorful one :-) Colors are explained +in the <a href="#color" target="_top">next sections</a>.</p> +<p>We can OR(|) any number of above attributes to get a combined +effect. If you wanted reverse video with blinking characters you +can use</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> attron(A_REVERSE | A_BLINK);</font> +</pre></td> +</tr> +</table> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="ATTRONVSATTRSET" id= +"ATTRONVSATTRSET">8.2. attron() vs attrset()</a></h3> +<p>Then what is the difference between attron() and attrset()? +attrset sets the attributes of window whereas attron just switches +on the attribute given to it. So attrset() fully overrides whatever +attributes the window previously had and sets it to the new +attribute(s). Similarly attroff() just switches off the +attribute(s) given to it as an argument. This gives us the +flexibility of managing attributes easily.But if you use them +carelessly you may loose track of what attributes the window has +and garble the display. This is especially true while managing +menus with colors and highlighting. So decide on a consistent +policy and stick to it. You can always use <var class= +"LITERAL">standend()</var> which is equivalent to <var class= +"LITERAL">attrset(A_NORMAL)</var> which turns off all attributes +and brings you to normal mode.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="ATTR_GET" id="ATTR_GET">8.3. +attr_get()</a></h3> +<p>The function attr_get() gets the current attributes and color +pair of the window. Though we might not use this as often as the +above functions, this is useful in scanning areas of screen. Say we +wanted to do some complex update on screen and we are not sure what +attribute each character is associated with. Then this function can +be used with either attrset or attron to produce the desired +effect.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="ATTR_FUNCS" id="ATTR_FUNCS">8.4. attr_ +functions</a></h3> +<p>There are series of functions like attr_set(), attr_on etc.. +These are similar to above functions except that they take +parameters of type <var class="LITERAL">attr_t</var>.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="WATTRFUNCS" id="WATTRFUNCS">8.5. wattr +functions</a></h3> +<p>For each of the above functions we have a corresponding function +with 'w' which operates on a particular window. The above functions +operate on stdscr.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="CHGAT" id="CHGAT">8.6. chgat() +functions</a></h3> +<p>The function chgat() is listed in the end of the man page +curs_attr. It actually is a useful one. This function can be used +to set attributes for a group of characters without moving. I mean +it !!! without moving the cursor :-) It changes the attributes of a +given number of characters starting at the current cursor +location.</p> +<p>We can give -1 as the character count to update till end of +line. If you want to change attributes of characters from current +position to end of line, just use this.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> chgat(-1, A_REVERSE, 0, NULL);</font> +</pre></td> +</tr> +</table> +<p>This function is useful when changing attributes for characters +that are already on the screen. Move to the character from which +you want to change and change the attribute.</p> +<p>Other functions wchgat(), mvchgat(), wchgat() behave similarly +except that the w functions operate on the particular window. The +mv functions first move the cursor then perform the work given to +them. Actually chgat is a macro which is replaced by a wchgat() +with stdscr as the window. Most of the "w-less" functions are +macros.</p> +<div class="EXAMPLE"><a name="BWICH" id="BWICH"></a> +<p><b>Example 6. Chgat() Usage example</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <ncurses.h> + +int main(int argc, char *argv[]) +{ initscr(); /* Start curses mode */ + start_color(); /* Start color functionality */ + + init_pair(1, COLOR_CYAN, COLOR_BLACK); + printw("A Big string which i didn't care to type fully "); + mvchgat(0, 0, -1, A_BLINK, 1, NULL); + /* + * First two parameters specify the position at which to start + * Third parameter number of characters to update. -1 means till + * end of line + * Forth parameter is the normal attribute you wanted to give + * to the charcter + * Fifth is the color index. It is the index given during init_pair() + * use 0 if you didn't want color + * Sixth one is always NULL + */ + refresh(); + getch(); + endwin(); /* End curses mode */ + return 0; +}</span></font> +</pre></td> +</tr> +</table> +</div> +<p>This example also introduces us to the color world of curses. +Colors will be explained in detail later. Use 0 for no color.</p> +</div> +</div> +<div class="SECT1"> +<hr> +<h2 class="SECT1"><a name="WINDOWS" id="WINDOWS">9. +Windows</a></h2> +<p>Windows form the most important concept in curses. You have seen +the standard window stdscr above where all the functions implicitly +operated on this window. Now to make design even a simplest GUI, +you need to resort to windows. The main reason you may want to use +windows is to manipulate parts of the screen separately, for better +efficiency, by updating only the windows that need to be changed +and for a better design. I would say the last reason is the most +important in going for windows. You should always strive for a +better and easy-to-manage design in your programs. If you are +writing big, complex GUIs this is of pivotal importance before you +start doing anything.</p> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="WINDOWBASICS" id="WINDOWBASICS">9.1. The +basics</a></h3> +<p>A Window can be created by calling the function <var class= +"LITERAL">newwin()</var>. It doesn't create any thing on the screen +actually. It allocates memory for a structure to manipulate the +window and updates the structure with data regarding the window +like it's size, beginy, beginx etc.. Hence in curses, a window is +just an abstraction of an imaginary window, which can be +manipulated independent of other parts of screen. The function +newwin() returns a pointer to structure WINDOW, which can be passed +to window related functions like wprintw() etc.. Finally the window +can be destroyed with delwin(). It will deallocate the memory +associated with the window structure.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="LETBEWINDOW" id="LETBEWINDOW">9.2. Let +there be a Window !!!</a></h3> +<p>What fun is it, if a window is created and we can't see it. So +the fun part begins by displaying the window. The function +<var class="LITERAL">box()</var> can be used to draw a border +around the window. Let's explore these functions in more detail in +this example.</p> +<div class="EXAMPLE"><a name="BWIBO" id="BWIBO"></a> +<p><b>Example 7. Window Border example</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <ncurses.h> + + +WINDOW *create_newwin(int height, int width, int starty, int startx); +void destroy_win(WINDOW *local_win); + +int main(int argc, char *argv[]) +{ WINDOW *my_win; + int startx, starty, width, height; + int ch; + + initscr(); /* Start curses mode */ + cbreak(); /* Line buffering disabled, Pass on + * everty thing to me */ + keypad(stdscr, TRUE); /* I need that nifty F1 */ + + height = 3; + width = 10; + starty = (LINES - height) / 2; /* Calculating for a center placement */ + startx = (COLS - width) / 2; /* of the window */ + printw("Press F1 to exit"); + refresh(); + my_win = create_newwin(height, width, starty, startx); + + while((ch = getch()) != KEY_F(1)) + { switch(ch) + { case KEY_LEFT: + destroy_win(my_win); + my_win = create_newwin(height, width, starty,--startx); + break; + case KEY_RIGHT: + destroy_win(my_win); + my_win = create_newwin(height, width, starty,++startx); + break; + case KEY_UP: + destroy_win(my_win); + my_win = create_newwin(height, width, --starty,startx); + break; + case KEY_DOWN: + destroy_win(my_win); + my_win = create_newwin(height, width, ++starty,startx); + break; + } + } + + endwin(); /* End curses mode */ + return 0; +} + +WINDOW *create_newwin(int height, int width, int starty, int startx) +{ WINDOW *local_win; + + local_win = newwin(height, width, starty, startx); + box(local_win, 0 , 0); /* 0, 0 gives default characters + * for the vertical and horizontal + * lines */ + wrefresh(local_win); /* Show that box */ + + return local_win; +} + +void destroy_win(WINDOW *local_win) +{ + /* box(local_win, ' ', ' '); : This won't produce the desired + * result of erasing the window. It will leave it's four corners + * and so an ugly remnant of window. + */ + wborder(local_win, ' ', ' ', ' ',' ',' ',' ',' ',' '); + /* The parameters taken are + * 1. win: the window on which to operate + * 2. ls: character to be used for the left side of the window + * 3. rs: character to be used for the right side of the window + * 4. ts: character to be used for the top side of the window + * 5. bs: character to be used for the bottom side of the window + * 6. tl: character to be used for the top left corner of the window + * 7. tr: character to be used for the top right corner of the window + * 8. bl: character to be used for the bottom left corner of the window + * 9. br: character to be used for the bottom right corner of the window + */ + wrefresh(local_win); + delwin(local_win); +}</span></font> +</pre></td> +</tr> +</table> +</div> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="BORDEREXEXPL" id="BORDEREXEXPL">9.3. +Explanation</a></h3> +<p>Don't scream. I know it's a big example. But I have to explain +some important things here :-). This program creates a rectangular +window that can be moved with left, right, up, down arrow keys. It +repeatedly creates and destroys windows as user press a key. Don't +go beyond the screen limits. Checking for those limits is left as +an exercise for the reader. Let's dissect it by line by line.</p> +<p>The <var class="LITERAL">create_newwin()</var> function creates +a window with <var class="LITERAL">newwin()</var> and displays a +border around it with box. The function <var class= +"LITERAL">destroy_win()</var> first erases the window from screen +by painting a border with ' ' character and then calling +<var class="LITERAL">delwin()</var> to deallocate memory related to +it. Depending on the key the user presses, starty or startx is +changed and a new window is created.</p> +<p>In the destroy_win, as you can see, I used wborder instead of +box. The reason is written in the comments (You missed it. I know. +Read the code :-)). wborder draws a border around the window with +the characters given to it as the 4 corner points and the 4 lines. +To put it clearly, if you have called wborder as below:</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000"> wborder(win, '|', '|', '-', '-', '+', '+', '+', '+');</font> +</pre></td> +</tr> +</table> +<p>it produces some thing like</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> +------------+ + | | + | | + | | + | | + | | + | | + +------------+</font> +</pre></td> +</tr> +</table> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="OTHERSTUFF" id="OTHERSTUFF">9.4. The +other stuff in the example</a></h3> +<p>You can also see in the above examples, that I have used the +variables COLS, LINES which are initialized to the screen sizes +after initscr(). They can be useful in finding screen dimensions +and finding the center co-ordinate of the screen as above. The +function <var class="LITERAL">getch()</var> as usual gets the key +from keyboard and according to the key it does the corresponding +work. This type of switch- case is very common in any GUI based +programs.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="OTHERBORDERFUNCS" id= +"OTHERBORDERFUNCS">9.5. Other Border functions</a></h3> +<p>Above program is grossly inefficient in that with each press of +a key, a window is destroyed and another is created. So let's write +a more efficient program which uses other border related +functions.</p> +<p>The following program uses <var class="LITERAL">mvhline()</var> +and <var class="LITERAL">mvvline()</var> to achieve similar effect. +These two functions are simple. They create a horizontal or +vertical line of the specified length at the specified +position.</p> +<div class="EXAMPLE"><a name="BOTBO" id="BOTBO"></a> +<p><b>Example 8. More border functions</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <ncurses.h> + +typedef struct _win_border_struct { + chtype ls, rs, ts, bs, + tl, tr, bl, br; +}WIN_BORDER; + +typedef struct _WIN_struct { + + int startx, starty; + int height, width; + WIN_BORDER border; +}WIN; + +void init_win_params(WIN *p_win); +void print_win_params(WIN *p_win); +void create_box(WIN *win, bool flag); + +int main(int argc, char *argv[]) +{ WIN win; + int ch; + + initscr(); /* Start curses mode */ + start_color(); /* Start the color functionality */ + cbreak(); /* Line buffering disabled, Pass on + * everty thing to me */ + keypad(stdscr, TRUE); /* I need that nifty F1 */ + noecho(); + init_pair(1, COLOR_CYAN, COLOR_BLACK); + + /* Initialize the window parameters */ + init_win_params(&win); + print_win_params(&win); + + attron(COLOR_PAIR(1)); + printw("Press F1 to exit"); + refresh(); + attroff(COLOR_PAIR(1)); + + create_box(&win, TRUE); + while((ch = getch()) != KEY_F(1)) + { switch(ch) + { case KEY_LEFT: + create_box(&win, FALSE); + --win.startx; + create_box(&win, TRUE); + break; + case KEY_RIGHT: + create_box(&win, FALSE); + ++win.startx; + create_box(&win, TRUE); + break; + case KEY_UP: + create_box(&win, FALSE); + --win.starty; + create_box(&win, TRUE); + break; + case KEY_DOWN: + create_box(&win, FALSE); + ++win.starty; + create_box(&win, TRUE); + break; + } + } + endwin(); /* End curses mode */ + return 0; +} +void init_win_params(WIN *p_win) +{ + p_win->height = 3; + p_win->width = 10; + p_win->starty = (LINES - p_win->height)/2; + p_win->startx = (COLS - p_win->width)/2; + + p_win->border.ls = '|'; + p_win->border.rs = '|'; + p_win->border.ts = '-'; + p_win->border.bs = '-'; + p_win->border.tl = '+'; + p_win->border.tr = '+'; + p_win->border.bl = '+'; + p_win->border.br = '+'; + +} +void print_win_params(WIN *p_win) +{ +#ifdef _DEBUG + mvprintw(25, 0, "%d %d %d %d", p_win->startx, p_win->starty, + p_win->width, p_win->height); + refresh(); +#endif +} +void create_box(WIN *p_win, bool flag) +{ int i, j; + int x, y, w, h; + + x = p_win->startx; + y = p_win->starty; + w = p_win->width; + h = p_win->height; + + if(flag == TRUE) + { mvaddch(y, x, p_win->border.tl); + mvaddch(y, x + w, p_win->border.tr); + mvaddch(y + h, x, p_win->border.bl); + mvaddch(y + h, x + w, p_win->border.br); + mvhline(y, x + 1, p_win->border.ts, w - 1); + mvhline(y + h, x + 1, p_win->border.bs, w - 1); + mvvline(y + 1, x, p_win->border.ls, h - 1); + mvvline(y + 1, x + w, p_win->border.rs, h - 1); + + } + else + for(j = y; j <= y + h; ++j) + for(i = x; i <= x + w; ++i) + mvaddch(j, i, ' '); + + refresh(); + +}</span></font> +</pre></td> +</tr> +</table> +</div> +</div> +</div> +<div class="SECT1"> +<hr> +<h2 class="SECT1"><a name="COLOR" id="COLOR">10. Colors</a></h2> +<div class="SECT2"> +<h3 class="SECT2"><a name="COLORBASICS" id="COLORBASICS">10.1. The +basics</a></h3> +<p>Life seems dull with no colors. Curses has a nice mechanism to +handle colors. Let's get into the thick of the things with a small +program.</p> +<div class="EXAMPLE"><a name="BSICO" id="BSICO"></a> +<p><b>Example 9. A Simple Color example</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <ncurses.h> + +void print_in_middle(WINDOW *win, int starty, int startx, int width, char *string); +int main(int argc, char *argv[]) +{ initscr(); /* Start curses mode */ + if(has_colors() == FALSE) + { endwin(); + printf("Your terminal does not support color\n"); + exit(1); + } + start_color(); /* Start color */ + init_pair(1, COLOR_RED, COLOR_BLACK); + + attron(COLOR_PAIR(1)); + print_in_middle(stdscr, LINES / 2, 0, 0, "Viola !!! In color ..."); + attroff(COLOR_PAIR(1)); + getch(); + endwin(); +} +void print_in_middle(WINDOW *win, int starty, int startx, int width, char *string) +{ int length, x, y; + float temp; + + if(win == NULL) + win = stdscr; + getyx(win, y, x); + if(startx != 0) + x = startx; + if(starty != 0) + y = starty; + if(width == 0) + width = 80; + + length = strlen(string); + temp = (width - length)/ 2; + x = startx + (int)temp; + mvwprintw(win, y, x, "%s", string); + refresh(); +} +</span></font> +</pre></td> +</tr> +</table> +</div> +<p>As you can see, to start using color, you should first call the +function <var class="LITERAL">start_color()</var>. After that, you +can use color capabilities of your terminals using various +functions. To find out whether a terminal has color capabilities or +not, you can use <var class="LITERAL">has_colors()</var> function, +which returns FALSE if the terminal does not support color.</p> +<p>Curses initializes all the colors supported by terminal when +start_color() is called. These can be accessed by the define +constants like <var class="LITERAL">COLOR_BLACK</var> etc. Now to +actually start using colors, you have to define pairs. Colors are +always used in pairs. That means you have to use the function +<var class="LITERAL">init_pair()</var> to define the foreground and +background for the pair number you give. After that that pair +number can be used as a normal attribute with <var class= +"LITERAL">COLOR_PAIR()</var>function. This may seem to be +cumbersome at first. But this elegant solution allows us to manage +color pairs very easily. To appreciate it, you have to look into +the the source code of "dialog", a utility for displaying dialog +boxes from shell scripts. The developers have defined foreground +and background combinations for all the colors they might need and +initialized at the beginning. This makes it very easy to set +attributes just by accessing a pair which we already have defined +as a constant.</p> +<p>The following colors are defined in <var class= +"LITERAL">curses.h</var>. You can use these as parameters for +various color functions.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> COLOR_BLACK 0 + COLOR_RED 1 + COLOR_GREEN 2 + COLOR_YELLOW 3 + COLOR_BLUE 4 + COLOR_MAGENTA 5 + COLOR_CYAN 6 + COLOR_WHITE 7</font> +</pre></td> +</tr> +</table> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="CHANGECOLORDEFS" id= +"CHANGECOLORDEFS">10.2. Changing Color Definitions</a></h3> +<p>The function <var class="LITERAL">init_color()</var>can be used +to change the rgb values for the colors defined by curses +initially. Say you wanted to lighten the intensity of red color by +a minuscule. Then you can use this function as</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> init_color(COLOR_RED, 700, 0, 0); + /* param 1 : color name + * param 2, 3, 4 : rgb content min = 0, max = 1000 */</font> +</pre></td> +</tr> +</table> +<p>If your terminal cannot change the color definitions, the +function returns ERR. The function <var class= +"LITERAL">can_change_color()</var> can be used to find out whether +the terminal has the capability of changing color content or not. +The rgb content is scaled from 0 to 1000. Initially RED color is +defined with content 1000(r), 0(g), 0(b).</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="COLORCONTENT" id="COLORCONTENT">10.3. +Color Content</a></h3> +<p>The functions <var class="LITERAL">color_content()</var> and +<var class="LITERAL">pair_content()</var> can be used to find the +color content and foreground, background combination for the +pair.</p> +</div> +</div> +<div class="SECT1"> +<hr> +<h2 class="SECT1"><a name="KEYS" id="KEYS">11. Interfacing with the +key board</a></h2> +<div class="SECT2"> +<h3 class="SECT2"><a name="KEYSBASICS" id="KEYSBASICS">11.1. The +Basics</a></h3> +<p>No GUI is complete without a strong user interface and to +interact with the user, a curses program should be sensitive to key +presses or the mouse actions done by the user. Let's deal with the +keys first.</p> +<p>As you have seen in almost all of the above examples, it's very +easy to get key input from the user. A simple way of getting key +presses is to use <var class="LITERAL">getch()</var> function. The +cbreak mode should be enabled to read keys when you are interested +in reading individual key hits rather than complete lines of text +(which usually end with a carriage return). keypad should be +enabled to get the Functions keys, arrow keys etc. See the +initialization section for details.</p> +<p><var class="LITERAL">getch()</var> returns an integer +corresponding to the key pressed. If it is a normal character, the +integer value will be equivalent to the character. Otherwise it +returns a number which can be matched with the constants defined in +<var class="LITERAL">curses.h</var>. For example if the user +presses F1, the integer returned is 265. This can be checked using +the macro KEY_F() defined in curses.h. This makes reading keys +portable and easy to manage.</p> +<p>For example, if you call getch() like this</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> int ch; + + ch = getch();</font> +</pre></td> +</tr> +</table> +<p>getch() will wait for the user to press a key, (unless you +specified a timeout) and when user presses a key, the corresponding +integer is returned. Then you can check the value returned with the +constants defined in curses.h to match against the keys you +want.</p> +<p>The following code piece will do that job.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> if(ch == KEY_LEFT) + printw("Left arrow is pressed\n");</font> +</pre></td> +</tr> +</table> +<p>Let's write a small program which creates a menu which can be +navigated by up and down arrows.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="SIMPLEKEYEX" id="SIMPLEKEYEX">11.2. A +Simple Key Usage example</a></h3> +<div class="EXAMPLE"><a name="BSIKE" id="BSIKE"></a> +<p><b>Example 10. A Simple Key Usage example</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <stdio.h> +#include <ncurses.h> + +#define WIDTH 30 +#define HEIGHT 10 + +int startx = 0; +int starty = 0; + +char *choices[] = { + "Choice 1", + "Choice 2", + "Choice 3", + "Choice 4", + "Exit", + }; +int n_choices = sizeof(choices) / sizeof(char *); +void print_menu(WINDOW *menu_win, int highlight); + +int main() +{ WINDOW *menu_win; + int highlight = 1; + int choice = 0; + int c; + + initscr(); + clear(); + noecho(); + cbreak(); /* Line buffering disabled. pass on everything */ + startx = (80 - WIDTH) / 2; + starty = (24 - HEIGHT) / 2; + + menu_win = newwin(HEIGHT, WIDTH, starty, startx); + keypad(menu_win, TRUE); + mvprintw(0, 0, "Use arrow keys to go up and down, Press enter to select a choice"); + refresh(); + print_menu(menu_win, highlight); + while(1) + { c = wgetch(menu_win); + switch(c) + { case KEY_UP: + if(highlight == 1) + highlight = n_choices; + else + --highlight; + break; + case KEY_DOWN: + if(highlight == n_choices) + highlight = 1; + else + ++highlight; + break; + case 10: + choice = highlight; + break; + default: + mvprintw(24, 0, "Charcter pressed is = %3d Hopefully it can be printed as '%c'", c, c); + refresh(); + break; + } + print_menu(menu_win, highlight); + if(choice != 0) /* User did a choice come out of the infinite loop */ + break; + } + mvprintw(23, 0, "You chose choice %d with choice string %s\n", choice, choices[choice - 1]); + clrtoeol(); + refresh(); + endwin(); + return 0; +} + + +void print_menu(WINDOW *menu_win, int highlight) +{ + int x, y, i; + + x = 2; + y = 2; + box(menu_win, 0, 0); + for(i = 0; i < n_choices; ++i) + { if(highlight == i + 1) /* High light the present choice */ + { wattron(menu_win, A_REVERSE); + mvwprintw(menu_win, y, x, "%s", choices[i]); + wattroff(menu_win, A_REVERSE); + } + else + mvwprintw(menu_win, y, x, "%s", choices[i]); + ++y; + } + wrefresh(menu_win); +} +</span></font> +</pre></td> +</tr> +</table> +</div> +</div> +</div> +<div class="SECT1"> +<hr> +<h2 class="SECT1"><a name="MOUSE" id="MOUSE">12. Interfacing with +the mouse</a></h2> +<p>Now that you have seen how to get keys, lets do the same thing +from mouse. Usually each UI allows the user to interact with both +keyboard and mouse.</p> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="MOUSEBASICS" id="MOUSEBASICS">12.1. The +Basics</a></h3> +<p>Before you do any thing else, the events you want to receive +have to be enabled with <var class="LITERAL">mousemask()</var>.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000"> mousemask( mmask_t newmask, /* The events you want to listen to */ + mmask_t *oldmask) /* The old events mask */</font> +</pre></td> +</tr> +</table> +<p>The first parameter to above function is a bit mask of events +you would like to listen. By default, all the events are turned +off. The bit mask <var class="LITERAL">ALL_MOUSE_EVENTS</var> can +be used to get all the events.</p> +<p>The following are all the event masks:</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> Name Description + --------------------------------------------------------------------- + BUTTON1_PRESSED mouse button 1 down + BUTTON1_RELEASED mouse button 1 up + BUTTON1_CLICKED mouse button 1 clicked + BUTTON1_DOUBLE_CLICKED mouse button 1 double clicked + BUTTON1_TRIPLE_CLICKED mouse button 1 triple clicked + BUTTON2_PRESSED mouse button 2 down + BUTTON2_RELEASED mouse button 2 up + BUTTON2_CLICKED mouse button 2 clicked + BUTTON2_DOUBLE_CLICKED mouse button 2 double clicked + BUTTON2_TRIPLE_CLICKED mouse button 2 triple clicked + BUTTON3_PRESSED mouse button 3 down + BUTTON3_RELEASED mouse button 3 up + BUTTON3_CLICKED mouse button 3 clicked + BUTTON3_DOUBLE_CLICKED mouse button 3 double clicked + BUTTON3_TRIPLE_CLICKED mouse button 3 triple clicked + BUTTON4_PRESSED mouse button 4 down + BUTTON4_RELEASED mouse button 4 up + BUTTON4_CLICKED mouse button 4 clicked + BUTTON4_DOUBLE_CLICKED mouse button 4 double clicked + BUTTON4_TRIPLE_CLICKED mouse button 4 triple clicked + BUTTON_SHIFT shift was down during button state change + BUTTON_CTRL control was down during button state change + BUTTON_ALT alt was down during button state change + ALL_MOUSE_EVENTS report all button state changes + REPORT_MOUSE_POSITION report mouse movement</font> +</pre></td> +</tr> +</table> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="GETTINGEVENTS" id="GETTINGEVENTS">12.2. +Getting the events</a></h3> +<p>Once a class of mouse events have been enabled, getch() class of +functions return KEY_MOUSE every time some mouse event happens. +Then the mouse event can be retrieved with <var class= +"LITERAL">getmouse()</var>.</p> +<p>The code approximately looks like this:</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> MEVENT event; + + ch = getch(); + if(ch == KEY_MOUSE) + if(getmouse(&event) == OK) + . /* Do some thing with the event */ + . + .</font> +</pre></td> +</tr> +</table> +<p>getmouse() returns the event into the pointer given to it. It's +a structure which contains</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> typedef struct + { + short id; /* ID to distinguish multiple devices */ + int x, y, z; /* event coordinates */ + mmask_t bstate; /* button state bits */ + } </font> +</pre></td> +</tr> +</table> +<p>The <var class="LITERAL">bstate</var> is the main variable we +are interested in. It tells the button state of the mouse.</p> +<p>Then with a code snippet like the following, we can find out +what happened.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> if(event.bstate & BUTTON1_PRESSED) + printw("Left Button Pressed");</font> +</pre></td> +</tr> +</table> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="MOUSETOGETHER" id="MOUSETOGETHER">12.3. +Putting it all Together</a></h3> +<p>That's pretty much interfacing with mouse. Let's create the same +menu and enable mouse interaction. To make things simpler, key +handling is removed.</p> +<div class="EXAMPLE"><a name="BMOME" id="BMOME"></a> +<p><b>Example 11. Access the menu with mouse !!!</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <ncurses.h> + +#define WIDTH 30 +#define HEIGHT 10 + +int startx = 0; +int starty = 0; + +char *choices[] = { "Choice 1", + "Choice 2", + "Choice 3", + "Choice 4", + "Exit", + }; + +int n_choices = sizeof(choices) / sizeof(char *); + +void print_menu(WINDOW *menu_win, int highlight); +void report_choice(int mouse_x, int mouse_y, int *p_choice); + +int main() +{ int c, choice = 0; + WINDOW *menu_win; + MEVENT event; + + /* Initialize curses */ + initscr(); + clear(); + noecho(); + cbreak(); //Line buffering disabled. pass on everything + + /* Try to put the window in the middle of screen */ + startx = (80 - WIDTH) / 2; + starty = (24 - HEIGHT) / 2; + + attron(A_REVERSE); + mvprintw(23, 1, "Click on Exit to quit (Works best in a virtual console)"); + refresh(); + attroff(A_REVERSE); + + /* Print the menu for the first time */ + menu_win = newwin(HEIGHT, WIDTH, starty, startx); + print_menu(menu_win, 1); + /* Get all the mouse events */ + mousemask(ALL_MOUSE_EVENTS, NULL); + + while(1) + { c = wgetch(menu_win); + switch(c) + { case KEY_MOUSE: + if(getmouse(&event) == OK) + { /* When the user clicks left mouse button */ + if(event.bstate & BUTTON1_PRESSED) + { report_choice(event.x + 1, event.y + 1, &choice); + if(choice == -1) //Exit chosen + goto end; + mvprintw(22, 1, "Choice made is : %d String Chosen is \"%10s\"", choice, choices[choice - 1]); + refresh(); + } + } + print_menu(menu_win, choice); + break; + } + } +end: + endwin(); + return 0; +} + + +void print_menu(WINDOW *menu_win, int highlight) +{ + int x, y, i; + + x = 2; + y = 2; + box(menu_win, 0, 0); + for(i = 0; i < n_choices; ++i) + { if(highlight == i + 1) + { wattron(menu_win, A_REVERSE); + mvwprintw(menu_win, y, x, "%s", choices[i]); + wattroff(menu_win, A_REVERSE); + } + else + mvwprintw(menu_win, y, x, "%s", choices[i]); + ++y; + } + wrefresh(menu_win); +} + +/* Report the choice according to mouse position */ +void report_choice(int mouse_x, int mouse_y, int *p_choice) +{ int i,j, choice; + + i = startx + 2; + j = starty + 3; + + for(choice = 0; choice < n_choices; ++choice) + if(mouse_y == j + choice && mouse_x >= i && mouse_x <= i + strlen(choices[choice])) + { if(choice == n_choices - 1) + *p_choice = -1; + else + *p_choice = choice + 1; + break; + } +}</span></font> +</pre></td> +</tr> +</table> +</div> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="MISCMOUSEFUNCS" id= +"MISCMOUSEFUNCS">12.4. Miscellaneous Functions</a></h3> +<p>The functions mouse_trafo() and wmouse_trafo() can be used to +convert to mouse co-ordinates to screen relative co-ordinates. See +curs_mouse(3X) man page for details.</p> +<p>The mouseinterval function sets the maximum time (in thousands +of a second) that can elapse between press and release events in +order for them to be recognized as a click. This function returns +the previous interval value. The default is one fifth of a +second.</p> +</div> +</div> +<div class="SECT1"> +<hr> +<h2 class="SECT1"><a name="SCREEN" id="SCREEN">13. Screen +Manipulation</a></h2> +<p>In this section, we will look into some functions, which allow +us to manage the screen efficiently and to write some fancy +programs. This is especially important in writing games.</p> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="GETYX" id="GETYX">13.1. getyx() +functions</a></h3> +<p>The function <var class="LITERAL">getyx()</var> can be used to +find out the present cursor co-ordinates. It will fill the values +of x and y co-ordinates in the arguments given to it. Since getyx() +is a macro you don't have to pass the address of the variables. It +can be called as</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> getyx(win, y, x); + /* win: window pointer + * y, x: y, x co-ordinates will be put into this variables + */</font> +</pre></td> +</tr> +</table> +<p>The function getparyx() gets the beginning co-ordinates of the +sub window relative to the main window. This is some times useful +to update a sub window. When designing fancy stuff like writing +multiple menus, it becomes difficult to store the menu positions, +their first option co-ordinates etc. A simple solution to this +problem, is to create menus in sub windows and later find the +starting co-ordinates of the menus by using getparyx().</p> +<p>The functions getbegyx() and getmaxyx() store current window's +beginning and maximum co-ordinates. These functions are useful in +the same way as above in managing the windows and sub windows +effectively.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="SCREENDUMP" id="SCREENDUMP">13.2. Screen +Dumping</a></h3> +<p>While writing games, some times it becomes necessary to store +the state of the screen and restore it back to the same state. The +function scr_dump() can be used to dump the screen contents to a +file given as an argument. Later it can be restored by scr_restore +function. These two simple functions can be used effectively to +maintain a fast moving game with changing scenarios.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="WINDOWDUMP" id="WINDOWDUMP">13.3. Window +Dumping</a></h3> +<p>To store and restore windows, the functions <var class= +"LITERAL">putwin()</var> and <var class="LITERAL">getwin()</var> +can be used. <var class="LITERAL">putwin()</var> puts the present +window state into a file, which can be later restored by +<var class="LITERAL">getwin()</var>.</p> +<p>The function <var class="LITERAL">copywin()</var> can be used to +copy a window completely onto another window. It takes the source +and destination windows as parameters and according to the +rectangle specified, it copies the rectangular region from source +to destination window. It's last parameter specifies whether to +overwrite or just overlay the contents on to the destination +window. If this argument is true, then the copying is +non-destructive.</p> +</div> +</div> +<div class="SECT1"> +<hr> +<h2 class="SECT1"><a name="MISC" id="MISC">14. Miscellaneous +features</a></h2> +<p>Now you know enough features to write a good curses program, +with all bells and whistles. There are some miscellaneous functions +which are useful in various cases. Let's go headlong into some of +those.</p> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="CURSSET" id="CURSSET">14.1. +curs_set()</a></h3> +<p>This function can be used to make the cursor invisible. The +parameter to this function should be</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> 0 : invisible or + 1 : normal or + 2 : very visible.</font> +</pre></td> +</tr> +</table> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="TEMPLEAVE" id="TEMPLEAVE">14.2. +Temporarily Leaving Curses mode</a></h3> +<p>Some times you may want to get back to cooked mode (normal line +buffering mode) temporarily. In such a case you will first need to +save the tty modes with a call to <var class= +"LITERAL">def_prog_mode()</var> and then call <var class= +"LITERAL">endwin()</var> to end the curses mode. This will leave +you in the original tty mode. To get back to curses once you are +done, call <var class="LITERAL">reset_prog_mode()</var> . This +function returns the tty to the state stored by <var class= +"LITERAL">def_prog_mode()</var>. Then do refresh(), and you are +back to the curses mode. Here is an example showing the sequence of +things to be done.</p> +<div class="EXAMPLE"><a name="BTELE" id="BTELE"></a> +<p><b>Example 12. Temporarily Leaving Curses Mode</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <ncurses.h> + +int main() +{ + initscr(); /* Start curses mode */ + printw("Hello World !!!\n"); /* Print Hello World */ + refresh(); /* Print it on to the real screen */ + def_prog_mode(); /* Save the tty modes */ + endwin(); /* End curses mode temporarily */ + system("/bin/sh"); /* Do whatever you like in cooked mode */ + reset_prog_mode(); /* Return to the previous tty mode*/ + /* stored by def_prog_mode() */ + refresh(); /* Do refresh() to restore the */ + /* Screen contents */ + printw("Another String\n"); /* Back to curses use the full */ + refresh(); /* capabilities of curses */ + endwin(); /* End curses mode */ + + return 0; +}</span></font> +</pre></td> +</tr> +</table> +</div> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="ACSVARS" id="ACSVARS">14.3. ACS_ +variables</a></h3> +<p>If you have ever programmed in DOS, you know about those nifty +characters in extended character set. They are printable only on +some terminals. NCURSES functions like <var class= +"LITERAL">box()</var> use these characters. All these variables +start with ACS meaning alternative character set. You might have +noticed me using these characters in some of the programs above. +Here's an example showing all the characters.</p> +<div class="EXAMPLE"><a name="BACSVARS" id="BACSVARS"></a> +<p><b>Example 13. ACS Variables Example</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <ncurses.h> + +int main() +{ + initscr(); + + printw("Upper left corner "); addch(ACS_ULCORNER); printw("\n"); + printw("Lower left corner "); addch(ACS_LLCORNER); printw("\n"); + printw("Lower right corner "); addch(ACS_LRCORNER); printw("\n"); + printw("Tee pointing right "); addch(ACS_LTEE); printw("\n"); + printw("Tee pointing left "); addch(ACS_RTEE); printw("\n"); + printw("Tee pointing up "); addch(ACS_BTEE); printw("\n"); + printw("Tee pointing down "); addch(ACS_TTEE); printw("\n"); + printw("Horizontal line "); addch(ACS_HLINE); printw("\n"); + printw("Vertical line "); addch(ACS_VLINE); printw("\n"); + printw("Large Plus or cross over "); addch(ACS_PLUS); printw("\n"); + printw("Scan Line 1 "); addch(ACS_S1); printw("\n"); + printw("Scan Line 3 "); addch(ACS_S3); printw("\n"); + printw("Scan Line 7 "); addch(ACS_S7); printw("\n"); + printw("Scan Line 9 "); addch(ACS_S9); printw("\n"); + printw("Diamond "); addch(ACS_DIAMOND); printw("\n"); + printw("Checker board (stipple) "); addch(ACS_CKBOARD); printw("\n"); + printw("Degree Symbol "); addch(ACS_DEGREE); printw("\n"); + printw("Plus/Minus Symbol "); addch(ACS_PLMINUS); printw("\n"); + printw("Bullet "); addch(ACS_BULLET); printw("\n"); + printw("Arrow Pointing Left "); addch(ACS_LARROW); printw("\n"); + printw("Arrow Pointing Right "); addch(ACS_RARROW); printw("\n"); + printw("Arrow Pointing Down "); addch(ACS_DARROW); printw("\n"); + printw("Arrow Pointing Up "); addch(ACS_UARROW); printw("\n"); + printw("Board of squares "); addch(ACS_BOARD); printw("\n"); + printw("Lantern Symbol "); addch(ACS_LANTERN); printw("\n"); + printw("Solid Square Block "); addch(ACS_BLOCK); printw("\n"); + printw("Less/Equal sign "); addch(ACS_LEQUAL); printw("\n"); + printw("Greater/Equal sign "); addch(ACS_GEQUAL); printw("\n"); + printw("Pi "); addch(ACS_PI); printw("\n"); + printw("Not equal "); addch(ACS_NEQUAL); printw("\n"); + printw("UK pound sign "); addch(ACS_STERLING); printw("\n"); + + refresh(); + getch(); + endwin(); + + return 0; +}</span></font> +</pre></td> +</tr> +</table> +</div> +</div> +</div> +<div class="SECT1"> +<hr> +<h2 class="SECT1"><a name="OTHERLIB" id="OTHERLIB">15. Other +libraries</a></h2> +<p>Apart from the curses library, there are few text mode +libraries, which provide more functionality and a lot of features. +The following sections explain three standard libraries which are +usually distributed along with curses.</p> +</div> +<div class="SECT1"> +<hr> +<h2 class="SECT1"><a name="PANELS" id="PANELS">16. Panel +Library</a></h2> +<p>Now that you are proficient in curses, you wanted to do some +thing big. You created a lot of overlapping windows to give a +professional windows-type look. Unfortunately, it soon becomes +difficult to manage these. The multiple refreshes, updates plunge +you into a nightmare. The overlapping windows create blotches, +whenever you forget to refresh the windows in the proper order.</p> +<p>Don't despair. There's an elegant solution provided in panels +library. In the words of developers of ncurses</p> +<p><em>When your interface design is such that windows may dive +deeper into the visibility stack or pop to the top at runtime, the +resulting book-keeping can be tedious and difficult to get right. +Hence the panels library.</em></p> +<p>If you have lot of overlapping windows, then panels library is +the way to go. It obviates the need of doing series of +wnoutrefresh(), doupdate() and relieves the burden of doing it +correctly(bottom up). The library maintains information about the +order of windows, their overlapping and update the screen properly. +So why wait? Let's take a close peek into panels.</p> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="PANELBASICS" id="PANELBASICS">16.1. The +Basics</a></h3> +<p>Panel object is a window that is implicitly treated as part of a +deck including all other panel objects. The deck is treated as a +stack with the top panel being completely visible and the other +panels may or may not be obscured according to their positions. So +the basic idea is to create a stack of overlapping panels and use +panels library to display them correctly. There is a function +similar to refresh() which, when called , displays panels in the +correct order. Functions are provided to hide or show panels, move +panels, change its size etc.. The overlapping problem is managed by +the panels library during all the calls to these functions.</p> +<p>The general flow of a panel program goes like this:</p> +<ol type="1"> +<li> +<p>Create the windows (with newwin()) to be attached to the +panels.</p> +</li> +<li> +<p>Create panels with the chosen visibility order. Stack them up +according to the desired visibility. The function new_panel() is +used to created panels.</p> +</li> +<li> +<p>Call update_panels() to write the panels to the virtual screen +in correct visibility order. Do a doupdate() to show it on the +screen.</p> +</li> +<li> +<p>Mainpulate the panels with show_panel(), hide_panel(), +move_panel() etc. Make use of helper functions like panel_hidden() +and panel_window(). Make use of user pointer to store custom data +for a panel. Use the functions set_panel_userptr() and +panel_userptr() to set and get the user pointer for a panel.</p> +</li> +<li> +<p>When you are done with the panel use del_panel() to delete the +panel.</p> +</li> +</ol> +<p>Let's make the concepts clear, with some programs. The following +is a simple program which creates 3 overlapping panels and shows +them on the screen.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="COMPILEPANELS" id="COMPILEPANELS">16.2. +Compiling With the Panels Library</a></h3> +<p>To use panels library functions, you have to include panel.h and +to link the program with panels library the flag -lpanel should be +added along with -lncurses in that order.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> #include <panel.h> + . + . + . + + compile and link: gcc <program file> -lpanel -lncurses</font> +</pre></td> +</tr> +</table> +<div class="EXAMPLE"><a name="PPASI" id="PPASI"></a> +<p><b>Example 14. Panel basics</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <panel.h> + +int main() +{ WINDOW *my_wins[3]; + PANEL *my_panels[3]; + int lines = 10, cols = 40, y = 2, x = 4, i; + + initscr(); + cbreak(); + noecho(); + + /* Create windows for the panels */ + my_wins[0] = newwin(lines, cols, y, x); + my_wins[1] = newwin(lines, cols, y + 1, x + 5); + my_wins[2] = newwin(lines, cols, y + 2, x + 10); + + /* + * Create borders around the windows so that you can see the effect + * of panels + */ + for(i = 0; i < 3; ++i) + box(my_wins[i], 0, 0); + + /* Attach a panel to each window */ /* Order is bottom up */ + my_panels[0] = new_panel(my_wins[0]); /* Push 0, order: stdscr-0 */ + my_panels[1] = new_panel(my_wins[1]); /* Push 1, order: stdscr-0-1 */ + my_panels[2] = new_panel(my_wins[2]); /* Push 2, order: stdscr-0-1-2 */ + + /* Update the stacking order. 2nd panel will be on top */ + update_panels(); + + /* Show it on the screen */ + doupdate(); + + getch(); + endwin(); +} +</span></font> +</pre></td> +</tr> +</table> +</div> +<p>As you can see, above program follows a simple flow as +explained. The windows are created with newwin() and then they are +attached to panels with new_panel(). As we attach one panel after +another, the stack of panels gets updated. To put them on screen +update_panels() and doupdate() are called.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="PANELBROWSING" id="PANELBROWSING">16.3. +Panel Window Browsing</a></h3> +<p>A slightly complicated example is given below. This program +creates 3 windows which can be cycled through using tab. Have a +look at the code.</p> +<div class="EXAMPLE"><a name="PPABR" id="PPABR"></a> +<p><b>Example 15. Panel Window Browsing Example</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <panel.h> + +#define NLINES 10 +#define NCOLS 40 + +void init_wins(WINDOW **wins, int n); +void win_show(WINDOW *win, char *label, int label_color); +void print_in_middle(WINDOW *win, int starty, int startx, int width, char *string, chtype color); + +int main() +{ WINDOW *my_wins[3]; + PANEL *my_panels[3]; + PANEL *top; + int ch; + + /* Initialize curses */ + initscr(); + start_color(); + cbreak(); + noecho(); + keypad(stdscr, TRUE); + + /* Initialize all the colors */ + init_pair(1, COLOR_RED, COLOR_BLACK); + init_pair(2, COLOR_GREEN, COLOR_BLACK); + init_pair(3, COLOR_BLUE, COLOR_BLACK); + init_pair(4, COLOR_CYAN, COLOR_BLACK); + + init_wins(my_wins, 3); + + /* Attach a panel to each window */ /* Order is bottom up */ + my_panels[0] = new_panel(my_wins[0]); /* Push 0, order: stdscr-0 */ + my_panels[1] = new_panel(my_wins[1]); /* Push 1, order: stdscr-0-1 */ + my_panels[2] = new_panel(my_wins[2]); /* Push 2, order: stdscr-0-1-2 */ + + /* Set up the user pointers to the next panel */ + set_panel_userptr(my_panels[0], my_panels[1]); + set_panel_userptr(my_panels[1], my_panels[2]); + set_panel_userptr(my_panels[2], my_panels[0]); + + /* Update the stacking order. 2nd panel will be on top */ + update_panels(); + + /* Show it on the screen */ + attron(COLOR_PAIR(4)); + mvprintw(LINES - 2, 0, "Use tab to browse through the windows (F1 to Exit)"); + attroff(COLOR_PAIR(4)); + doupdate(); + + top = my_panels[2]; + while((ch = getch()) != KEY_F(1)) + { switch(ch) + { case 9: + top = (PANEL *)panel_userptr(top); + top_panel(top); + break; + } + update_panels(); + doupdate(); + } + endwin(); + return 0; +} + +/* Put all the windows */ +void init_wins(WINDOW **wins, int n) +{ int x, y, i; + char label[80]; + + y = 2; + x = 10; + for(i = 0; i < n; ++i) + { wins[i] = newwin(NLINES, NCOLS, y, x); + sprintf(label, "Window Number %d", i + 1); + win_show(wins[i], label, i + 1); + y += 3; + x += 7; + } +} + +/* Show the window with a border and a label */ +void win_show(WINDOW *win, char *label, int label_color) +{ int startx, starty, height, width; + + getbegyx(win, starty, startx); + getmaxyx(win, height, width); + + box(win, 0, 0); + mvwaddch(win, 2, 0, ACS_LTEE); + mvwhline(win, 2, 1, ACS_HLINE, width - 2); + mvwaddch(win, 2, width - 1, ACS_RTEE); + + print_in_middle(win, 1, 0, width, label, COLOR_PAIR(label_color)); +} + +void print_in_middle(WINDOW *win, int starty, int startx, int width, char *string, chtype color) +{ int length, x, y; + float temp; + + if(win == NULL) + win = stdscr; + getyx(win, y, x); + if(startx != 0) + x = startx; + if(starty != 0) + y = starty; + if(width == 0) + width = 80; + + length = strlen(string); + temp = (width - length)/ 2; + x = startx + (int)temp; + wattron(win, color); + mvwprintw(win, y, x, "%s", string); + wattroff(win, color); + refresh(); +}</span></font> +</pre></td> +</tr> +</table> +</div> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="USERPTRUSING" id="USERPTRUSING">16.4. +Using User Pointers</a></h3> +<p>In the above example I used user pointers to find out the next +window in the cycle. We can attach custom information to the panel +by specifying a user pointer, which can point to any information +you want to store. In this case I stored the pointer to the next +panel in the cycle. User pointer for a panel can be set with the +function <var class="LITERAL">set_panel_userptr()</var>. It can be +accessed using the function <var class= +"LITERAL">panel_userptr()</var> which will return the user pointer +for the panel given as argument. After finding the next panel in +the cycle It's brought to the top by the function top_panel(). This +function brings the panel given as argument to the top of the panel +stack.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="PANELMOVERESIZE" id= +"PANELMOVERESIZE">16.5. Moving and Resizing Panels</a></h3> +<p>The function <var class="LITERAL">move_panel()</var> can be used +to move a panel to the desired location. It does not change the +position of the panel in the stack. Make sure that you use +move_panel() instead mvwin() on the window associated with the +panel.</p> +<p>Resizing a panel is slightly complex. There is no straight +forward function just to resize the window associated with a panel. +A solution to resize a panel is to create a new window with the +desired sizes, change the window associated with the panel using +replace_panel(). Don't forget to delete the old window. The window +associated with a panel can be found by using the function +panel_window().</p> +<p>The following program shows these concepts, in supposedly simple +program. You can cycle through the window with <TAB> as +usual. To resize or move the active panel press 'r' for resize 'm' +for moving. Then use arrow keys to resize or move it to the desired +way and press enter to end your resizing or moving. This example +makes use of user data to get the required data to do the +operations.</p> +<div class="EXAMPLE"><a name="PPARE" id="PPARE"></a> +<p><b>Example 16. Panel Moving and Resizing example</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <panel.h> + +typedef struct _PANEL_DATA { + int x, y, w, h; + char label[80]; + int label_color; + PANEL *next; +}PANEL_DATA; + +#define NLINES 10 +#define NCOLS 40 + +void init_wins(WINDOW **wins, int n); +void win_show(WINDOW *win, char *label, int label_color); +void print_in_middle(WINDOW *win, int starty, int startx, int width, char *string, chtype color); +void set_user_ptrs(PANEL **panels, int n); + +int main() +{ WINDOW *my_wins[3]; + PANEL *my_panels[3]; + PANEL_DATA *top; + PANEL *stack_top; + WINDOW *temp_win, *old_win; + int ch; + int newx, newy, neww, newh; + int size = FALSE, move = FALSE; + + /* Initialize curses */ + initscr(); + start_color(); + cbreak(); + noecho(); + keypad(stdscr, TRUE); + + /* Initialize all the colors */ + init_pair(1, COLOR_RED, COLOR_BLACK); + init_pair(2, COLOR_GREEN, COLOR_BLACK); + init_pair(3, COLOR_BLUE, COLOR_BLACK); + init_pair(4, COLOR_CYAN, COLOR_BLACK); + + init_wins(my_wins, 3); + + /* Attach a panel to each window */ /* Order is bottom up */ + my_panels[0] = new_panel(my_wins[0]); /* Push 0, order: stdscr-0 */ + my_panels[1] = new_panel(my_wins[1]); /* Push 1, order: stdscr-0-1 */ + my_panels[2] = new_panel(my_wins[2]); /* Push 2, order: stdscr-0-1-2 */ + + set_user_ptrs(my_panels, 3); + /* Update the stacking order. 2nd panel will be on top */ + update_panels(); + + /* Show it on the screen */ + attron(COLOR_PAIR(4)); + mvprintw(LINES - 3, 0, "Use 'm' for moving, 'r' for resizing"); + mvprintw(LINES - 2, 0, "Use tab to browse through the windows (F1 to Exit)"); + attroff(COLOR_PAIR(4)); + doupdate(); + + stack_top = my_panels[2]; + top = (PANEL_DATA *)panel_userptr(stack_top); + newx = top->x; + newy = top->y; + neww = top->w; + newh = top->h; + while((ch = getch()) != KEY_F(1)) + { switch(ch) + { case 9: /* Tab */ + top = (PANEL_DATA *)panel_userptr(stack_top); + top_panel(top->next); + stack_top = top->next; + top = (PANEL_DATA *)panel_userptr(stack_top); + newx = top->x; + newy = top->y; + neww = top->w; + newh = top->h; + break; + case 'r': /* Re-Size*/ + size = TRUE; + attron(COLOR_PAIR(4)); + mvprintw(LINES - 4, 0, "Entered Resizing :Use Arrow Keys to resize and press <ENTER> to end resizing"); + refresh(); + attroff(COLOR_PAIR(4)); + break; + case 'm': /* Move */ + attron(COLOR_PAIR(4)); + mvprintw(LINES - 4, 0, "Entered Moving: Use Arrow Keys to Move and press <ENTER> to end moving"); + refresh(); + attroff(COLOR_PAIR(4)); + move = TRUE; + break; + case KEY_LEFT: + if(size == TRUE) + { --newx; + ++neww; + } + if(move == TRUE) + --newx; + break; + case KEY_RIGHT: + if(size == TRUE) + { ++newx; + --neww; + } + if(move == TRUE) + ++newx; + break; + case KEY_UP: + if(size == TRUE) + { --newy; + ++newh; + } + if(move == TRUE) + --newy; + break; + case KEY_DOWN: + if(size == TRUE) + { ++newy; + --newh; + } + if(move == TRUE) + ++newy; + break; + case 10: /* Enter */ + move(LINES - 4, 0); + clrtoeol(); + refresh(); + if(size == TRUE) + { old_win = panel_window(stack_top); + temp_win = newwin(newh, neww, newy, newx); + replace_panel(stack_top, temp_win); + win_show(temp_win, top->label, top->label_color); + delwin(old_win); + size = FALSE; + } + if(move == TRUE) + { move_panel(stack_top, newy, newx); + move = FALSE; + } + break; + + } + attron(COLOR_PAIR(4)); + mvprintw(LINES - 3, 0, "Use 'm' for moving, 'r' for resizing"); + mvprintw(LINES - 2, 0, "Use tab to browse through the windows (F1 to Exit)"); + attroff(COLOR_PAIR(4)); + refresh(); + update_panels(); + doupdate(); + } + endwin(); + return 0; +} + +/* Put all the windows */ +void init_wins(WINDOW **wins, int n) +{ int x, y, i; + char label[80]; + + y = 2; + x = 10; + for(i = 0; i < n; ++i) + { wins[i] = newwin(NLINES, NCOLS, y, x); + sprintf(label, "Window Number %d", i + 1); + win_show(wins[i], label, i + 1); + y += 3; + x += 7; + } +} + +/* Set the PANEL_DATA structures for individual panels */ +void set_user_ptrs(PANEL **panels, int n) +{ PANEL_DATA *ptrs; + WINDOW *win; + int x, y, w, h, i; + char temp[80]; + + ptrs = (PANEL_DATA *)calloc(n, sizeof(PANEL_DATA)); + + for(i = 0;i < n; ++i) + { win = panel_window(panels[i]); + getbegyx(win, y, x); + getmaxyx(win, h, w); + ptrs[i].x = x; + ptrs[i].y = y; + ptrs[i].w = w; + ptrs[i].h = h; + sprintf(temp, "Window Number %d", i + 1); + strcpy(ptrs[i].label, temp); + ptrs[i].label_color = i + 1; + if(i + 1 == n) + ptrs[i].next = panels[0]; + else + ptrs[i].next = panels[i + 1]; + set_panel_userptr(panels[i], &ptrs[i]); + } +} + +/* Show the window with a border and a label */ +void win_show(WINDOW *win, char *label, int label_color) +{ int startx, starty, height, width; + + getbegyx(win, starty, startx); + getmaxyx(win, height, width); + + box(win, 0, 0); + mvwaddch(win, 2, 0, ACS_LTEE); + mvwhline(win, 2, 1, ACS_HLINE, width - 2); + mvwaddch(win, 2, width - 1, ACS_RTEE); + + print_in_middle(win, 1, 0, width, label, COLOR_PAIR(label_color)); +} + +void print_in_middle(WINDOW *win, int starty, int startx, int width, char *string, chtype color) +{ int length, x, y; + float temp; + + if(win == NULL) + win = stdscr; + getyx(win, y, x); + if(startx != 0) + x = startx; + if(starty != 0) + y = starty; + if(width == 0) + width = 80; + + length = strlen(string); + temp = (width - length)/ 2; + x = startx + (int)temp; + wattron(win, color); + mvwprintw(win, y, x, "%s", string); + wattroff(win, color); + refresh(); +}</span></font> +</pre></td> +</tr> +</table> +</div> +<p>Concentrate on the main while loop. Once it finds out the type +of key pressed, it takes appropriate action. If 'r' is pressed +resizing mode is started. After this the new sizes are updated as +the user presses the arrow keys. When the user presses +<ENTER> present selection ends and panel is resized by using +the concept explained. While in resizing mode the program doesn't +show how the window is getting resized. It's left as an exercise to +the reader to print a dotted border while it gets resized to a new +position.</p> +<p>When the user presses 'm' the move mode starts. This is a bit +simpler than resizing. As the arrow keys are pressed the new +position is updated and pressing of <ENTER> causes the panel +to be moved by calling the function move_panel().</p> +<p>In this program the user data which is represented as +PANEL_DATA, plays very important role in finding the associated +information with a panel. As written in the comments, the +PANEL_DATA stores the panel sizes, label, label color and a pointer +to the next panel in the cycle.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="PANELSHOWHIDE" id="PANELSHOWHIDE">16.6. +Hiding and Showing Panels</a></h3> +<p>A Panel can be hidden by using the function hide_panel(). This +function merely removes it form the stack of panels, thus hiding it +on the screen once you do update_panels() and doupdate(). It +doesn't destroy the PANEL structure associated with the hidden +panel. It can be shown again by using the show_panel() +function.</p> +<p>The following program shows the hiding of panels. Press 'a' or +'b' or 'c' to show or hide first, second and third windows +respectively. It uses a user data with a small variable hide, which +keeps track of whether the window is hidden or not. For some reason +the function <var class="LITERAL">panel_hidden()</var> which tells +whether a panel is hidden or not is not working. A bug report was +also presented by Michael Andres <a href= +"http://www.geocrawler.com/archives/3/344/1999/9/0/2643549/" +target="_top">here</a></p> +<div class="EXAMPLE"><a name="PPAHI" id="PPAHI"></a> +<p><b>Example 17. Panel Hiding and Showing example</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <panel.h> + +typedef struct _PANEL_DATA { + int hide; /* TRUE if panel is hidden */ +}PANEL_DATA; + +#define NLINES 10 +#define NCOLS 40 + +void init_wins(WINDOW **wins, int n); +void win_show(WINDOW *win, char *label, int label_color); +void print_in_middle(WINDOW *win, int starty, int startx, int width, char *string, chtype color); + +int main() +{ WINDOW *my_wins[3]; + PANEL *my_panels[3]; + PANEL_DATA panel_datas[3]; + PANEL_DATA *temp; + int ch; + + /* Initialize curses */ + initscr(); + start_color(); + cbreak(); + noecho(); + keypad(stdscr, TRUE); + + /* Initialize all the colors */ + init_pair(1, COLOR_RED, COLOR_BLACK); + init_pair(2, COLOR_GREEN, COLOR_BLACK); + init_pair(3, COLOR_BLUE, COLOR_BLACK); + init_pair(4, COLOR_CYAN, COLOR_BLACK); + + init_wins(my_wins, 3); + + /* Attach a panel to each window */ /* Order is bottom up */ + my_panels[0] = new_panel(my_wins[0]); /* Push 0, order: stdscr-0 */ + my_panels[1] = new_panel(my_wins[1]); /* Push 1, order: stdscr-0-1 */ + my_panels[2] = new_panel(my_wins[2]); /* Push 2, order: stdscr-0-1-2 */ + + /* Initialize panel datas saying that nothing is hidden */ + panel_datas[0].hide = FALSE; + panel_datas[1].hide = FALSE; + panel_datas[2].hide = FALSE; + + set_panel_userptr(my_panels[0], &panel_datas[0]); + set_panel_userptr(my_panels[1], &panel_datas[1]); + set_panel_userptr(my_panels[2], &panel_datas[2]); + + /* Update the stacking order. 2nd panel will be on top */ + update_panels(); + + /* Show it on the screen */ + attron(COLOR_PAIR(4)); + mvprintw(LINES - 3, 0, "Show or Hide a window with 'a'(first window) 'b'(Second Window) 'c'(Third Window)"); + mvprintw(LINES - 2, 0, "F1 to Exit"); + + attroff(COLOR_PAIR(4)); + doupdate(); + + while((ch = getch()) != KEY_F(1)) + { switch(ch) + { case 'a': + temp = (PANEL_DATA *)panel_userptr(my_panels[0]); + if(temp->hide == FALSE) + { hide_panel(my_panels[0]); + temp->hide = TRUE; + } + else + { show_panel(my_panels[0]); + temp->hide = FALSE; + } + break; + case 'b': + temp = (PANEL_DATA *)panel_userptr(my_panels[1]); + if(temp->hide == FALSE) + { hide_panel(my_panels[1]); + temp->hide = TRUE; + } + else + { show_panel(my_panels[1]); + temp->hide = FALSE; + } + break; + case 'c': + temp = (PANEL_DATA *)panel_userptr(my_panels[2]); + if(temp->hide == FALSE) + { hide_panel(my_panels[2]); + temp->hide = TRUE; + } + else + { show_panel(my_panels[2]); + temp->hide = FALSE; + } + break; + } + update_panels(); + doupdate(); + } + endwin(); + return 0; +} + +/* Put all the windows */ +void init_wins(WINDOW **wins, int n) +{ int x, y, i; + char label[80]; + + y = 2; + x = 10; + for(i = 0; i < n; ++i) + { wins[i] = newwin(NLINES, NCOLS, y, x); + sprintf(label, "Window Number %d", i + 1); + win_show(wins[i], label, i + 1); + y += 3; + x += 7; + } +} + +/* Show the window with a border and a label */ +void win_show(WINDOW *win, char *label, int label_color) +{ int startx, starty, height, width; + + getbegyx(win, starty, startx); + getmaxyx(win, height, width); + + box(win, 0, 0); + mvwaddch(win, 2, 0, ACS_LTEE); + mvwhline(win, 2, 1, ACS_HLINE, width - 2); + mvwaddch(win, 2, width - 1, ACS_RTEE); + + print_in_middle(win, 1, 0, width, label, COLOR_PAIR(label_color)); +} + +void print_in_middle(WINDOW *win, int starty, int startx, int width, char *string, chtype color) +{ int length, x, y; + float temp; + + if(win == NULL) + win = stdscr; + getyx(win, y, x); + if(startx != 0) + x = startx; + if(starty != 0) + y = starty; + if(width == 0) + width = 80; + + length = strlen(string); + temp = (width - length)/ 2; + x = startx + (int)temp; + wattron(win, color); + mvwprintw(win, y, x, "%s", string); + wattroff(win, color); + refresh(); +}</span></font> +</pre></td> +</tr> +</table> +</div> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="PANELABOVE" id="PANELABOVE">16.7. +panel_above() and panel_below() Functions</a></h3> +<p>The functions <var class="LITERAL">panel_above()</var> and +<var class="LITERAL">panel_below()</var> can be used to find out +the panel above and below a panel. If the argument to these +functions is NULL, then they return a pointer to bottom panel and +top panel respectively.</p> +</div> +</div> +<div class="SECT1"> +<hr> +<h2 class="SECT1"><a name="MENUS" id="MENUS">17. Menus +Library</a></h2> +<p>The menus library provides a nice extension to basic curses, +through which you can create menus. It provides a set of functions +to create menus. But they have to be customized to give a nicer +look, with colors etc. Let's get into the details.</p> +<p>A menu is a screen display that assists the user to choose some +subset of a given set of items. To put it simple, a menu is a +collection of items from which one or more items can be chosen. +Some readers might not be aware of multiple item selection +capability. Menu library provides functionality to write menus from +which the user can chose more than one item as the preferred +choice. This is dealt with in a later section. Now it is time for +some rudiments.</p> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="MENUBASICS" id="MENUBASICS">17.1. The +Basics</a></h3> +<p>To create menus, you first create items, and then post the menu +to the display. After that, all the processing of user responses is +done in an elegant function menu_driver() which is the work horse +of any menu program.</p> +<p>The general flow of control of a menu program looks like +this.</p> +<ol type="1"> +<li> +<p>Initialize curses</p> +</li> +<li> +<p>Create items using new_item(). You can specify a name and +description for the items.</p> +</li> +<li> +<p>Create the menu with new_menu() by specifying the items to be +attached with.</p> +</li> +<li> +<p>Post the menu with menu_post() and refresh the screen.</p> +</li> +<li> +<p>Process the user requests with a loop and do necessary updates +to menu with menu_driver.</p> +</li> +<li> +<p>Unpost the menu with menu_unpost()</p> +</li> +<li> +<p>Free the memory allocated to menu by free_menu()</p> +</li> +<li> +<p>Free the memory allocated to the items with free_item()</p> +</li> +<li> +<p>End curses</p> +</li> +</ol> +<p>Let's see a program which prints a simple menu and updates the +current selection with up, down arrows.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="COMPILEMENUS" id="COMPILEMENUS">17.2. +Compiling With the Menu Library</a></h3> +<p>To use menu library functions, you have to include menu.h and to +link the program with menu library the flag -lmenu should be added +along with -lncurses in that order.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> #include <menu.h> + . + . + . + + compile and link: gcc <program file> -lmenu -lncurses</font> +</pre></td> +</tr> +</table> +<div class="EXAMPLE"><a name="MMESI" id="MMESI"></a> +<p><b>Example 18. Menu Basics</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <curses.h> +#include <menu.h> + +#define ARRAY_SIZE(a) (sizeof(a) / sizeof(a[0])) +#define CTRLD 4 + +char *choices[] = { + "Choice 1", + "Choice 2", + "Choice 3", + "Choice 4", + "Exit", + }; + +int main() +{ ITEM **my_items; + int c; + MENU *my_menu; + int n_choices, i; + ITEM *cur_item; + + + initscr(); + cbreak(); + noecho(); + keypad(stdscr, TRUE); + + n_choices = ARRAY_SIZE(choices); + my_items = (ITEM **)calloc(n_choices + 1, sizeof(ITEM *)); + + for(i = 0; i < n_choices; ++i) + my_items[i] = new_item(choices[i], choices[i]); + my_items[n_choices] = (ITEM *)NULL; + + my_menu = new_menu((ITEM **)my_items); + mvprintw(LINES - 2, 0, "F1 to Exit"); + post_menu(my_menu); + refresh(); + + while((c = getch()) != KEY_F(1)) + { switch(c) + { case KEY_DOWN: + menu_driver(my_menu, REQ_DOWN_ITEM); + break; + case KEY_UP: + menu_driver(my_menu, REQ_UP_ITEM); + break; + } + } + + free_item(my_items[0]); + free_item(my_items[1]); + free_menu(my_menu); + endwin(); +} + </span></font> +</pre></td> +</tr> +</table> +</div> +<p>This program demonstrates the basic concepts involved in +creating a menu using menus library. First we create the items +using new_item() and then attach them to the menu with new_menu() +function. After posting the menu and refreshing the screen, the +main processing loop starts. It reads user input and takes +corresponding action. The function menu_driver() is the main work +horse of the menu system. The second parameter to this function +tells what's to be done with the menu. According to the parameter, +menu_driver() does the corresponding task. The value can be either +a menu navigational request, an ascii character, or a KEY_MOUSE +special key associated with a mouse event.</p> +<p>The menu_driver accepts following navigational requests.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000"> 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 buffer. + REQ_NEXT_MATCH Move to the next item matching the pattern match. + REQ_PREV_MATCH Move to the previous item matching the pattern match. </font> +</pre></td> +</tr> +</table> +<p>Don't get overwhelmed by the number of options. We will see them +slowly one after another. The options of interest in this example +are REQ_UP_ITEM and REQ_DOWN_ITEM. These two options when passed to +menu_driver, menu driver updates the current item to one item up or +down respectively.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="MENUDRIVER" id="MENUDRIVER">17.3. Menu +Driver: The work horse of the menu system</a></h3> +<p>As you have seen in the above example, menu_driver plays an +important role in updating the menu. It is very important to +understand various options it takes and what they do. As explained +above, the second parameter to menu_driver() can be either a +navigational request, a printable character or a KEY_MOUSE key. +Let's dissect the different navigational requests.</p> +<ul> +<li> +<p><em>REQ_LEFT_ITEM and REQ_RIGHT_ITEM</em></p> +<p>A Menu can be displayed with multiple columns for more than one +item. This can be done by using the <var class= +"LITERAL">menu_format()</var>function. When a multi columnar menu +is displayed these requests cause the menu driver to move the +current selection to left or right.</p> +</li> +<li> +<p><em>REQ_UP_ITEM and REQ_DOWN_ITEM</em></p> +<p>These two options you have seen in the above example. These +options when given, makes the menu_driver to move the current +selection to an item up or down.</p> +</li> +<li> +<p><em>REQ_SCR_* options</em></p> +<p>The four options REQ_SCR_ULINE, REQ_SCR_DLINE, REQ_SCR_DPAGE, +REQ_SCR_UPAGE are related to scrolling. If all the items in the +menu cannot be displayed in the menu sub window, then the menu is +scrollable. These requests can be given to the menu_driver to do +the scrolling either one line up, down or one page down or up +respectively.</p> +</li> +<li> +<p><em>REQ_FIRST_ITEM, REQ_LAST_ITEM, REQ_NEXT_ITEM and +REQ_PREV_ITEM</em></p> +<p>These requests are self explanatory.</p> +</li> +<li> +<p><em>REQ_TOGGLE_ITEM</em></p> +<p>This request when given, toggles the present selection. This +option is to be used only in a multi valued menu. So to use this +request the option O_ONEVALUE must be off. This option can be made +off or on with set_menu_opts().</p> +</li> +<li> +<p><em>Pattern Requests</em></p> +<p>Every menu has an associated pattern buffer, which is used to +find the nearest match to the ascii characters entered by the user. +Whenever ascii characters are given to menu_driver, it puts in to +the pattern buffer. It also tries to find the nearest match to the +pattern in the items list and moves current selection to that item. +The request REQ_CLEAR_PATTERN clears the pattern buffer. The +request REQ_BACK_PATTERN deletes the previous character in the +pattern buffer. In case the pattern matches more than one item then +the matched items can be cycled through REQ_NEXT_MATCH and +REQ_PREV_MATCH which move the current selection to the next and +previous matches respectively.</p> +</li> +<li> +<p><em>Mouse Requests</em></p> +<p>In case of KEY_MOUSE requests, according to the mouse position +an action is taken accordingly. The action to be taken is explained +in the man page as,</p> +<table border="0" bgcolor="#E0E0E0" width="90%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000"><em> 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, a REQ_SCR_ULINE is generated, if you + doubleclick a REQ_SCR_UPAGE is generated and if you + tripleclick a REQ_FIRST_ITEM is generated. If you click + below the display region of the menu, a REQ_SCR_DLINE is + generated, if you doubleclick a REQ_SCR_DPAGE is generated + and if you tripleclick a REQ_LAST_ITEM is generated. If + you click at an item inside the display area of the menu, + the menu cursor is positioned to that item.</em></font> +</pre></td> +</tr> +</table> +</li> +</ul> +<p>Each of the above requests will be explained in the following +lines with several examples whenever appropriate.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="MENUWINDOWS" id="MENUWINDOWS">17.4. Menu +Windows</a></h3> +<p>Every menu created is associated with a window and a sub window. +The menu window displays any title or border associated with the +menu. The menu sub window displays the menu items currently +available for selection. But we didn't specify any window or sub +window in the simple example. When a window is not specified, +stdscr is taken as the main window, and then menu system calculates +the sub window size required for the display of items. Then items +are displayed in the calculated sub window. So let's play with +these windows and display a menu with a border and a title.</p> +<div class="EXAMPLE"><a name="MMEWI" id="MMEWI"></a> +<p><b>Example 19. Menu Windows Usage example</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <menu.h> + +#define ARRAY_SIZE(a) (sizeof(a) / sizeof(a[0])) +#define CTRLD 4 + +char *choices[] = { + "Choice 1", + "Choice 2", + "Choice 3", + "Choice 4", + "Exit", + (char *)NULL, + }; +void print_in_middle(WINDOW *win, int starty, int startx, int width, char *string, chtype color); + +int main() +{ ITEM **my_items; + int c; + MENU *my_menu; + WINDOW *my_menu_win; + int n_choices, i; + + /* Initialize curses */ + initscr(); + start_color(); + cbreak(); + noecho(); + keypad(stdscr, TRUE); + init_pair(1, COLOR_RED, COLOR_BLACK); + + /* Create items */ + n_choices = ARRAY_SIZE(choices); + my_items = (ITEM **)calloc(n_choices, sizeof(ITEM *)); + for(i = 0; i < n_choices; ++i) + my_items[i] = new_item(choices[i], choices[i]); + + /* Crate menu */ + my_menu = new_menu((ITEM **)my_items); + + /* Create the window to be associated with the menu */ + my_menu_win = newwin(10, 40, 4, 4); + keypad(my_menu_win, TRUE); + + /* Set main window and sub window */ + set_menu_win(my_menu, my_menu_win); + set_menu_sub(my_menu, derwin(my_menu_win, 6, 38, 3, 1)); + + /* Set menu mark to the string " * " */ + set_menu_mark(my_menu, " * "); + + /* Print a border around the main window and print a title */ + box(my_menu_win, 0, 0); + print_in_middle(my_menu_win, 1, 0, 40, "My Menu", COLOR_PAIR(1)); + mvwaddch(my_menu_win, 2, 0, ACS_LTEE); + mvwhline(my_menu_win, 2, 1, ACS_HLINE, 38); + mvwaddch(my_menu_win, 2, 39, ACS_RTEE); + mvprintw(LINES - 2, 0, "F1 to exit"); + refresh(); + + /* Post the menu */ + post_menu(my_menu); + wrefresh(my_menu_win); + + while((c = wgetch(my_menu_win)) != KEY_F(1)) + { switch(c) + { case KEY_DOWN: + menu_driver(my_menu, REQ_DOWN_ITEM); + break; + case KEY_UP: + menu_driver(my_menu, REQ_UP_ITEM); + break; + } + wrefresh(my_menu_win); + } + + /* Unpost and free all the memory taken up */ + unpost_menu(my_menu); + free_menu(my_menu); + for(i = 0; i < n_choices; ++i) + free_item(my_items[i]); + endwin(); +} + +void print_in_middle(WINDOW *win, int starty, int startx, int width, char *string, chtype color) +{ int length, x, y; + float temp; + + if(win == NULL) + win = stdscr; + getyx(win, y, x); + if(startx != 0) + x = startx; + if(starty != 0) + y = starty; + if(width == 0) + width = 80; + + length = strlen(string); + temp = (width - length)/ 2; + x = startx + (int)temp; + wattron(win, color); + mvwprintw(win, y, x, "%s", string); + wattroff(win, color); + refresh(); +}</span></font> +</pre></td> +</tr> +</table> +</div> +<p>This example creates a menu with a title, border, a fancy line +separating title and the items. As you can see, in order to attach +a window to a menu the function set_menu_win() has to be used. Then +we attach the sub window also. This displays the items in the sub +window. You can also set the mark string which gets displayed to +the left of the selected item with set_menu_mark().</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="SCROLLMENUS" id="SCROLLMENUS">17.5. +Scrolling Menus</a></h3> +<p>If the sub window given for a window is not big enough to show +all the items, then the menu will be scrollable. When you are on +the last item in the present list, if you send REQ_DOWN_ITEM, it +gets translated into REQ_SCR_DLINE and the menu scrolls by one +item. You can manually give REQ_SCR_ operations to do scrolling. +Let's see how it can be done.</p> +<div class="EXAMPLE"><a name="MMESC" id="MMESC"></a> +<p><b>Example 20. Scrolling Menus example</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <curses.h> +#include <menu.h> + +#define ARRAY_SIZE(a) (sizeof(a) / sizeof(a[0])) +#define CTRLD 4 + +char *choices[] = { + "Choice 1", + "Choice 2", + "Choice 3", + "Choice 4", + "Choice 5", + "Choice 6", + "Choice 7", + "Choice 8", + "Choice 9", + "Choice 10", + "Exit", + (char *)NULL, + }; +void print_in_middle(WINDOW *win, int starty, int startx, int width, char *string, chtype color); + +int main() +{ ITEM **my_items; + int c; + MENU *my_menu; + WINDOW *my_menu_win; + int n_choices, i; + + /* Initialize curses */ + initscr(); + start_color(); + cbreak(); + noecho(); + keypad(stdscr, TRUE); + init_pair(1, COLOR_RED, COLOR_BLACK); + init_pair(2, COLOR_CYAN, COLOR_BLACK); + + /* Create items */ + n_choices = ARRAY_SIZE(choices); + my_items = (ITEM **)calloc(n_choices, sizeof(ITEM *)); + for(i = 0; i < n_choices; ++i) + my_items[i] = new_item(choices[i], choices[i]); + + /* Crate menu */ + my_menu = new_menu((ITEM **)my_items); + + /* Create the window to be associated with the menu */ + my_menu_win = newwin(10, 40, 4, 4); + keypad(my_menu_win, TRUE); + + /* Set main window and sub window */ + set_menu_win(my_menu, my_menu_win); + set_menu_sub(my_menu, derwin(my_menu_win, 6, 38, 3, 1)); + set_menu_format(my_menu, 5, 1); + + /* Set menu mark to the string " * " */ + set_menu_mark(my_menu, " * "); + + /* Print a border around the main window and print a title */ + box(my_menu_win, 0, 0); + print_in_middle(my_menu_win, 1, 0, 40, "My Menu", COLOR_PAIR(1)); + mvwaddch(my_menu_win, 2, 0, ACS_LTEE); + mvwhline(my_menu_win, 2, 1, ACS_HLINE, 38); + mvwaddch(my_menu_win, 2, 39, ACS_RTEE); + + /* Post the menu */ + post_menu(my_menu); + wrefresh(my_menu_win); + + attron(COLOR_PAIR(2)); + mvprintw(LINES - 2, 0, "Use PageUp and PageDown to scoll down or up a page of items"); + mvprintw(LINES - 1, 0, "Arrow Keys to navigate (F1 to Exit)"); + attroff(COLOR_PAIR(2)); + refresh(); + + while((c = wgetch(my_menu_win)) != KEY_F(1)) + { switch(c) + { case KEY_DOWN: + menu_driver(my_menu, REQ_DOWN_ITEM); + break; + case KEY_UP: + menu_driver(my_menu, REQ_UP_ITEM); + break; + case KEY_NPAGE: + menu_driver(my_menu, REQ_SCR_DPAGE); + break; + case KEY_PPAGE: + menu_driver(my_menu, REQ_SCR_UPAGE); + break; + } + wrefresh(my_menu_win); + } + + /* Unpost and free all the memory taken up */ + unpost_menu(my_menu); + free_menu(my_menu); + for(i = 0; i < n_choices; ++i) + free_item(my_items[i]); + endwin(); +} + +void print_in_middle(WINDOW *win, int starty, int startx, int width, char *string, chtype color) +{ int length, x, y; + float temp; + + if(win == NULL) + win = stdscr; + getyx(win, y, x); + if(startx != 0) + x = startx; + if(starty != 0) + y = starty; + if(width == 0) + width = 80; + + length = strlen(string); + temp = (width - length)/ 2; + x = startx + (int)temp; + wattron(win, color); + mvwprintw(win, y, x, "%s", string); + wattroff(win, color); + refresh(); +}</span></font> +</pre></td> +</tr> +</table> +</div> +<p>This program is self-explanatory. In this example the number of +choices has been increased to ten, which is larger than our sub +window size which can hold 6 items. This message has to be +explicitly conveyed to the menu system with the function +set_menu_format(). In here we specify the number of rows and +columns we want to be displayed for a single page. We can specify +any number of items to be shown, in the rows variables, if it is +less than the height of the sub window. If the key pressed by the +user is a PAGE UP or PAGE DOWN, the menu is scrolled a page due to +the requests (REQ_SCR_DPAGE and REQ_SCR_UPAGE) given to +menu_driver().</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="MULTICOLUMN" id="MULTICOLUMN">17.6. +Multi Columnar Menus</a></h3> +<p>In the above example you have seen how to use the function +set_menu_format(). I didn't mention what the cols variable (third +parameter) does. Well, If your sub window is wide enough, you can +opt to display more than one item per row. This can be specified in +the cols variable. To make things simpler, the following example +doesn't show descriptions for the items.</p> +<div class="EXAMPLE"><a name="MMEMUCO" id="MMEMUCO"></a> +<p><b>Example 21. Milt Columnar Menus Example</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <curses.h> +#include <menu.h> + +#define ARRAY_SIZE(a) (sizeof(a) / sizeof(a[0])) +#define CTRLD 4 + +char *choices[] = { + "Choice 1", "Choice 2", "Choice 3", "Choice 4", "Choice 5", + "Choice 6", "Choice 7", "Choice 8", "Choice 9", "Choice 10", + "Choice 11", "Choice 12", "Choice 13", "Choice 14", "Choice 15", + "Choice 16", "Choice 17", "Choice 18", "Choice 19", "Choice 20", + "Exit", + (char *)NULL, + }; + +int main() +{ ITEM **my_items; + int c; + MENU *my_menu; + WINDOW *my_menu_win; + int n_choices, i; + + /* Initialize curses */ + initscr(); + start_color(); + cbreak(); + noecho(); + keypad(stdscr, TRUE); + init_pair(1, COLOR_RED, COLOR_BLACK); + init_pair(2, COLOR_CYAN, COLOR_BLACK); + + /* Create items */ + n_choices = ARRAY_SIZE(choices); + my_items = (ITEM **)calloc(n_choices, sizeof(ITEM *)); + for(i = 0; i < n_choices; ++i) + my_items[i] = new_item(choices[i], choices[i]); + + /* Crate menu */ + my_menu = new_menu((ITEM **)my_items); + + /* Set menu option not to show the description */ + menu_opts_off(my_menu, O_SHOWDESC); + + /* Create the window to be associated with the menu */ + my_menu_win = newwin(10, 70, 4, 4); + keypad(my_menu_win, TRUE); + + /* Set main window and sub window */ + set_menu_win(my_menu, my_menu_win); + set_menu_sub(my_menu, derwin(my_menu_win, 6, 68, 3, 1)); + set_menu_format(my_menu, 5, 3); + set_menu_mark(my_menu, " * "); + + /* Print a border around the main window and print a title */ + box(my_menu_win, 0, 0); + + attron(COLOR_PAIR(2)); + mvprintw(LINES - 3, 0, "Use PageUp and PageDown to scroll"); + mvprintw(LINES - 2, 0, "Use Arrow Keys to navigate (F1 to Exit)"); + attroff(COLOR_PAIR(2)); + refresh(); + + /* Post the menu */ + post_menu(my_menu); + wrefresh(my_menu_win); + + while((c = wgetch(my_menu_win)) != KEY_F(1)) + { switch(c) + { case KEY_DOWN: + menu_driver(my_menu, REQ_DOWN_ITEM); + break; + case KEY_UP: + menu_driver(my_menu, REQ_UP_ITEM); + break; + case KEY_LEFT: + menu_driver(my_menu, REQ_LEFT_ITEM); + break; + case KEY_RIGHT: + menu_driver(my_menu, REQ_RIGHT_ITEM); + break; + case KEY_NPAGE: + menu_driver(my_menu, REQ_SCR_DPAGE); + break; + case KEY_PPAGE: + menu_driver(my_menu, REQ_SCR_UPAGE); + break; + } + wrefresh(my_menu_win); + } + + /* Unpost and free all the memory taken up */ + unpost_menu(my_menu); + free_menu(my_menu); + for(i = 0; i < n_choices; ++i) + free_item(my_items[i]); + endwin(); +}</span></font> +</pre></td> +</tr> +</table> +</div> +<p>Watch the function call to set_menu_format(). It specifies the +number of columns to be 3, thus displaying 3 items per row. We have +also switched off the showing descriptions with the function +menu_opts_off(). There are couple of functions set_menu_opts(), +menu_opts_on() and menu_opts() which can be used to manipulate menu +options. The following menu options can be specified.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> O_ONEVALUE + Only one item can be selected for this menu. + + O_SHOWDESC + Display the item descriptions when the menu is + posted. + + O_ROWMAJOR + Display the menu in row-major order. + + O_IGNORECASE + Ignore the case when pattern-matching. + + O_SHOWMATCH + Move the cursor to within the item name while pat­ + tern-matching. + + O_NONCYCLIC + Don't wrap around next-item and previous-item, + requests to the other end of the menu.</font> +</pre></td> +</tr> +</table> +<p>All options are on by default. You can switch specific +attributes on or off with menu_opts_on() and menu_opts_off() +functions. You can also use set_menu_opts() to directly specify the +options. The argument to this function should be a OR ed value of +some of those above constants. The function menu_opts() can be used +to find out a menu's present options.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="MULTIVALUEMENUS" id= +"MULTIVALUEMENUS">17.7. Multi Valued Menus</a></h3> +<p>You might be wondering what if you switch off the option +O_ONEVALUE. Then the menu becomes multi-valued. That means you can +select more than one item. This brings us to the request +REQ_TOGGLE_ITEM. Let's see it in action.</p> +<div class="EXAMPLE"><a name="MMETO" id="MMETO"></a> +<p><b>Example 22. Multi Valued Menus example</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <curses.h> +#include <menu.h> + +#define ARRAY_SIZE(a) (sizeof(a) / sizeof(a[0])) +#define CTRLD 4 + +char *choices[] = { + "Choice 1", + "Choice 2", + "Choice 3", + "Choice 4", + "Choice 5", + "Choice 6", + "Choice 7", + "Exit", + }; + +int main() +{ ITEM **my_items; + int c; + MENU *my_menu; + int n_choices, i; + ITEM *cur_item; + + /* Initialize curses */ + initscr(); + cbreak(); + noecho(); + keypad(stdscr, TRUE); + + /* Initialize items */ + n_choices = ARRAY_SIZE(choices); + my_items = (ITEM **)calloc(n_choices + 1, sizeof(ITEM *)); + for(i = 0; i < n_choices; ++i) + my_items[i] = new_item(choices[i], choices[i]); + my_items[n_choices] = (ITEM *)NULL; + + my_menu = new_menu((ITEM **)my_items); + + /* Make the menu multi valued */ + menu_opts_off(my_menu, O_ONEVALUE); + + mvprintw(LINES - 3, 0, "Use <SPACE> to select or unselect an item."); + mvprintw(LINES - 2, 0, "<ENTER> to see presently selected items(F1 to Exit)"); + post_menu(my_menu); + refresh(); + + while((c = getch()) != KEY_F(1)) + { switch(c) + { case KEY_DOWN: + menu_driver(my_menu, REQ_DOWN_ITEM); + break; + case KEY_UP: + menu_driver(my_menu, REQ_UP_ITEM); + break; + case ' ': + menu_driver(my_menu, REQ_TOGGLE_ITEM); + break; + case 10: /* Enter */ + { char temp[200]; + ITEM **items; + + items = menu_items(my_menu); + temp[0] = '\0'; + for(i = 0; i < item_count(my_menu); ++i) + if(item_value(items[i]) == TRUE) + { strcat(temp, item_name(items[i])); + strcat(temp, " "); + } + move(20, 0); + clrtoeol(); + mvprintw(20, 0, temp); + refresh(); + } + break; + } + } + + free_item(my_items[0]); + free_item(my_items[1]); + free_menu(my_menu); + endwin(); +} + </span></font> +</pre></td> +</tr> +</table> +</div> +<p>Whew, A lot of new functions. Let's take them one after another. +Firstly, the REQ_TOGGLE_ITEM. In a multi-valued menu, the user +should be allowed to select or un select more than one item. The +request REQ_TOGGLE_ITEM toggles the present selection. In this case +when space is pressed REQ_TOGGLE_ITEM request is sent to +menu_driver to achieve the result.</p> +<p>Now when the user presses <ENTER> we show the items he +presently selected. First we find out the items associated with the +menu using the function menu_items(). Then we loop through the +items to find out if the item is selected or not. The function +item_value() returns TRUE if an item is selected. The function +item_count() returns the number of items in the menu. The item name +can be found with item_name(). You can also find the description +associated with an item using item_description().</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="MENUOPT" id="MENUOPT">17.8. Menu +Options</a></h3> +<p>Well, by this time you must be itching for some difference in +your menu, with lots of functionality. I know. You want Colors !!!. +You want to create nice menus similar to those text mode <a href= +"http://www.jersey.net/~debinjoe/games/" target="_top">dos +games</a>. The functions set_menu_fore() and set_menu_back() can be +used to change the attribute of the selected item and unselected +item. The names are misleading. They don't change menu's foreground +or background which would have been useless.</p> +<p>The function set_menu_grey() can be used to set the display +attribute for the non-selectable items in the menu. This brings us +to the interesting option for an item the one and only +O_SELECTABLE. We can turn it off by the function item_opts_off() +and after that that item is not selectable. It's like a grayed item +in those fancy windows menus. Let's put these concepts in practice +with this example</p> +<div class="EXAMPLE"><a name="MMEAT" id="MMEAT"></a> +<p><b>Example 23. Menu Options example</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <menu.h> + +#define ARRAY_SIZE(a) (sizeof(a) / sizeof(a[0])) +#define CTRLD 4 + +char *choices[] = { + "Choice 1", + "Choice 2", + "Choice 3", + "Choice 4", + "Choice 5", + "Choice 6", + "Choice 7", + "Exit", + }; + +int main() +{ ITEM **my_items; + int c; + MENU *my_menu; + int n_choices, i; + ITEM *cur_item; + + /* Initialize curses */ + initscr(); + start_color(); + cbreak(); + noecho(); + keypad(stdscr, TRUE); + init_pair(1, COLOR_RED, COLOR_BLACK); + init_pair(2, COLOR_GREEN, COLOR_BLACK); + init_pair(3, COLOR_MAGENTA, COLOR_BLACK); + + /* Initialize items */ + n_choices = ARRAY_SIZE(choices); + my_items = (ITEM **)calloc(n_choices + 1, sizeof(ITEM *)); + for(i = 0; i < n_choices; ++i) + my_items[i] = new_item(choices[i], choices[i]); + my_items[n_choices] = (ITEM *)NULL; + item_opts_off(my_items[3], O_SELECTABLE); + item_opts_off(my_items[6], O_SELECTABLE); + + /* Create menu */ + my_menu = new_menu((ITEM **)my_items); + + /* Set fore ground and back ground of the menu */ + set_menu_fore(my_menu, COLOR_PAIR(1) | A_REVERSE); + set_menu_back(my_menu, COLOR_PAIR(2)); + set_menu_grey(my_menu, COLOR_PAIR(3)); + + /* Post the menu */ + mvprintw(LINES - 3, 0, "Press <ENTER> to see the option selected"); + mvprintw(LINES - 2, 0, "Up and Down arrow keys to naviage (F1 to Exit)"); + post_menu(my_menu); + refresh(); + + while((c = getch()) != KEY_F(1)) + { switch(c) + { case KEY_DOWN: + menu_driver(my_menu, REQ_DOWN_ITEM); + break; + case KEY_UP: + menu_driver(my_menu, REQ_UP_ITEM); + break; + case 10: /* Enter */ + move(20, 0); + clrtoeol(); + mvprintw(20, 0, "Item selected is : %s", + item_name(current_item(my_menu))); + pos_menu_cursor(my_menu); + break; + } + } + unpost_menu(my_menu); + for(i = 0; i < n_choices; ++i) + free_item(my_items[i]); + free_menu(my_menu); + endwin(); +} + </span></font> +</pre></td> +</tr> +</table> +</div> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="MENUUSERPTR" id="MENUUSERPTR">17.9. The +useful User Pointer</a></h3> +<p>We can associate a user pointer with each item in the menu. It +works the same way as user pointer in panels. It's not touched by +menu system. You can store any thing you like in that. I usually +use it to store the function to be executed when the menu option is +chosen (It's selected and may be the user pressed +<ENTER>);</p> +<div class="EXAMPLE"><a name="MMEUS" id="MMEUS"></a> +<p><b>Example 24. Menu User Pointer Usage</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <curses.h> +#include <menu.h> + +#define ARRAY_SIZE(a) (sizeof(a) / sizeof(a[0])) +#define CTRLD 4 + +char *choices[] = { + "Choice 1", + "Choice 2", + "Choice 3", + "Choice 4", + "Choice 5", + "Choice 6", + "Choice 7", + "Exit", + }; +void func(char *name); + +int main() +{ ITEM **my_items; + int c; + MENU *my_menu; + int n_choices, i; + ITEM *cur_item; + + /* Initialize curses */ + initscr(); + start_color(); + cbreak(); + noecho(); + keypad(stdscr, TRUE); + init_pair(1, COLOR_RED, COLOR_BLACK); + init_pair(2, COLOR_GREEN, COLOR_BLACK); + init_pair(3, COLOR_MAGENTA, COLOR_BLACK); + + /* Initialize items */ + n_choices = ARRAY_SIZE(choices); + my_items = (ITEM **)calloc(n_choices + 1, sizeof(ITEM *)); + for(i = 0; i < n_choices; ++i) + { my_items[i] = new_item(choices[i], choices[i]); + /* Set the user pointer */ + set_item_userptr(my_items[i], func); + } + my_items[n_choices] = (ITEM *)NULL; + + /* Create menu */ + my_menu = new_menu((ITEM **)my_items); + + /* Post the menu */ + mvprintw(LINES - 3, 0, "Press <ENTER> to see the option selected"); + mvprintw(LINES - 2, 0, "Up and Down arrow keys to naviage (F1 to Exit)"); + post_menu(my_menu); + refresh(); + + while((c = getch()) != KEY_F(1)) + { switch(c) + { case KEY_DOWN: + menu_driver(my_menu, REQ_DOWN_ITEM); + break; + case KEY_UP: + menu_driver(my_menu, REQ_UP_ITEM); + break; + case 10: /* Enter */ + { ITEM *cur; + void (*p)(char *); + + cur = current_item(my_menu); + p = item_userptr(cur); + p((char *)item_name(cur)); + pos_menu_cursor(my_menu); + break; + } + break; + } + } + unpost_menu(my_menu); + for(i = 0; i < n_choices; ++i) + free_item(my_items[i]); + free_menu(my_menu); + endwin(); +} + +void func(char *name) +{ move(20, 0); + clrtoeol(); + mvprintw(20, 0, "Item selected is : %s", name); +} </span></font> +</pre></td> +</tr> +</table> +</div> +</div> +</div> +<div class="SECT1"> +<hr> +<h2 class="SECT1"><a name="FORMS" id="FORMS">18. Forms +Library</a></h2> +<p>Well. If you have seen those forms on web pages which take input +from users and do various kinds of things, you might be wondering +how would any one create such forms in text mode display. It's +quite difficult to write those nifty forms in plain ncurses. Forms +library tries to provide a basic frame work to build and maintain +forms with ease. It has lot of features(functions) which manage +validation, dynamic expansion of fields etc.. Let's see it in full +flow.</p> +<p>A form is a collection of fields; each field can be either a +label(static text) or a data-entry location. The forms also library +provides functions to divide forms into multiple pages.</p> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="FORMBASICS" id="FORMBASICS">18.1. The +Basics</a></h3> +<p>Forms are created in much the same way as menus. First the +fields related to the form are created with new_field(). You can +set options for the fields, so that they can be displayed with some +fancy attributes, validated before the field looses focus etc.. +Then the fields are attached to form. After this, the form can be +posted to display and is ready to receive inputs. On the similar +lines to menu_driver(), the form is manipulated with form_driver(). +We can send requests to form_driver to move focus to a certain +field, move cursor to end of the field etc.. After the user enters +values in the fields and validation done, form can be unposted and +memory allocated can be freed.</p> +<p>The general flow of control of a forms program looks like +this.</p> +<ol type="1"> +<li> +<p>Initialize curses</p> +</li> +<li> +<p>Create fields using new_field(). You can specify the height and +width of the field, and its position on the form.</p> +</li> +<li> +<p>Create the forms with new_form() by specifying the fields to be +attached with.</p> +</li> +<li> +<p>Post the form with form_post() and refresh the screen.</p> +</li> +<li> +<p>Process the user requests with a loop and do necessary updates +to form with form_driver.</p> +</li> +<li> +<p>Unpost the menu with form_unpost()</p> +</li> +<li> +<p>Free the memory allocated to menu by free_form()</p> +</li> +<li> +<p>Free the memory allocated to the items with free_field()</p> +</li> +<li> +<p>End curses</p> +</li> +</ol> +<p>As you can see, working with forms library is much similar to +handling menu library. The following examples will explore various +aspects of form processing. Let's start the journey with a simple +example. first.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="COMPILEFORMS" id="COMPILEFORMS">18.2. +Compiling With the Forms Library</a></h3> +<p>To use forms library functions, you have to include form.h and +to link the program with forms library the flag -lform should be +added along with -lncurses in that order.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"> #include <form.h> + . + . + . + + compile and link: gcc <program file> -lform -lncurses</font> +</pre></td> +</tr> +</table> +<div class="EXAMPLE"><a name="FFOSI" id="FFOSI"></a> +<p><b>Example 25. Forms Basics</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <form.h> + +int main() +{ FIELD *field[3]; + FORM *my_form; + int ch; + + /* Initialize curses */ + initscr(); + cbreak(); + noecho(); + keypad(stdscr, TRUE); + + /* Initialize the fields */ + field[0] = new_field(1, 10, 4, 18, 0, 0); + field[1] = new_field(1, 10, 6, 18, 0, 0); + field[2] = NULL; + + /* Set field options */ + set_field_back(field[0], A_UNDERLINE); /* Print a line for the option */ + field_opts_off(field[0], O_AUTOSKIP); /* Don't go to next field when this */ + /* Field is filled up */ + set_field_back(field[1], A_UNDERLINE); + field_opts_off(field[1], O_AUTOSKIP); + + /* Create the form and post it */ + my_form = new_form(field); + post_form(my_form); + refresh(); + + mvprintw(4, 10, "Value 1:"); + mvprintw(6, 10, "Value 2:"); + refresh(); + + /* Loop through to get user requests */ + while((ch = getch()) != KEY_F(1)) + { switch(ch) + { case KEY_DOWN: + /* Go to next field */ + form_driver(my_form, REQ_NEXT_FIELD); + /* Go to the end of the present buffer */ + /* Leaves nicely at the last character */ + form_driver(my_form, REQ_END_LINE); + break; + case KEY_UP: + /* Go to previous field */ + form_driver(my_form, REQ_PREV_FIELD); + form_driver(my_form, REQ_END_LINE); + break; + default: + /* If this is a normal character, it gets */ + /* Printed */ + form_driver(my_form, ch); + break; + } + } + + /* Un post form and free the memory */ + unpost_form(my_form); + free_form(my_form); + free_field(field[0]); + free_field(field[1]); + + endwin(); + return 0; +}</span></font> +</pre></td> +</tr> +</table> +</div> +<p>Above example is pretty straight forward. It creates two fields +with <var class="LITERAL">new_field()</var>. new_field() takes +height, width, starty, startx, number of offscreen rows and number +of additional working buffers. The fifth argument number of +offscreen rows specifies how much of the field to be shown. If it +is zero, the entire field is always displayed otherwise the form +will be scrollable when the user accesses not displayed parts of +the field. The forms library allocates one buffer per field to +store the data user enters. Using the last parameter to new_field() +we can specify it to allocate some additional buffers. These can be +used for any purpose you like.</p> +<p>After creating the fields, back ground attribute of both of them +is set to an underscore with set_field_back(). The AUTOSKIP option +is turned off using field_opts_off(). If this option is turned on, +focus will move to the next field in the form once the active field +is filled up completely.</p> +<p>After attaching the fields to the form, it is posted. Here on, +user inputs are processed in the while loop, by making +corresponding requests to form_driver. The details of all the +requests to the form_driver() are explained later.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="PLAYFIELDS" id="PLAYFIELDS">18.3. +Playing with Fields</a></h3> +<p>Each form field is associated with a lot of attributes. They can +be manipulated to get the required effect and to have fun !!!. So +why wait?</p> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="FETCHINFO" id="FETCHINFO">18.3.1. +Fetching Size and Location of Field</a></h4> +<p>The parameters we have given at the time of creation of a field +can be retrieved with field_info(). It returns height, width, +starty, startx, number of offscreen rows, and number of additional +buffers into the parameters given to it. It is a sort of inverse of +new_field().</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000">int field_info( FIELD *field, /* field from which to fetch */ + int *height, *int width, /* field size */ + int *top, int *left, /* upper left corner */ + int *offscreen, /* number of offscreen rows */ + int *nbuf); /* number of working buffers */</font> +</pre></td> +</tr> +</table> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="MOVEFIELD" id="MOVEFIELD">18.3.2. Moving +the field</a></h4> +<p>The location of the field can be moved to a different position +with move_field().</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000">int move_field( FIELD *field, /* field to alter */ + int top, int left); /* new upper-left corner */</font> +</pre></td> +</tr> +</table> +<p>As usual, the changed position can be queried with +field_infor().</p> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="JUSTIFYFIELD" id="JUSTIFYFIELD">18.3.3. +Field Justification</a></h4> +<p>The justification to be done for the field can be fixed using +the function set_field_just().</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000"> int set_field_just(FIELD *field, /* field to alter */ + int justmode); /* mode to set */ + int field_just(FIELD *field); /* fetch justify mode of field */</font> +</pre></td> +</tr> +</table> +<p>The justification mode valued accepted and returned by these +functions are NO_JUSTIFICATION, JUSTIFY_RIGHT, JUSTIFY_LEFT, or +JUSTIFY_CENTER.</p> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="FIELDDISPATTRIB" id= +"FIELDDISPATTRIB">18.3.4. Field Display Attributes</a></h4> +<p>As you have seen, in the above example, display attribute for +the fields can be set with set_field_fore() and setfield_back(). +These functions set foreground and background attribute of the +fields. You can also specify a pad character which will be filled +in the unfilled portion of the field. The pad character is set with +a call to set_field_pad(). Default pad value is a space. The +functions field_fore(), field_back, field_pad() can be used to +query the present foreground, background attributes and pad +character for the field. The following list gives the usage of +functions.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000"> int set_field_fore(FIELD *field, /* field to alter */ + chtype attr); /* attribute to set */ + +chtype field_fore(FIELD *field); /* field to query */ + /* returns foreground attribute */ + +int set_field_back(FIELD *field, /* field to alter */ + chtype attr); /* attribute to set */ + +chtype field_back(FIELD *field); /* field to query */ + /* returns background attribute */ + +int set_field_pad(FIELD *field, /* field to alter */ + int pad); /* pad character to set */ + +chtype field_pad(FIELD *field); /* field to query */ + /* returns present pad character */ </font> +</pre></td> +</tr> +</table> +<p>Though above functions seem quite simple, using colors with +set_field_fore() may be frustrating in the beginning. Let me first +explain about foreground and background attributes of a field. The +foreground attribute is associated with the character. That means a +character in the field is printed with the attribute you have set +with set_field_fore(). Background attribute is the attribute used +to fill background of field, whether any character is there or not. +So what about colors? Since colors are always defined in pairs, +what is the right way to display colored fields? Here's an example +clarifying color attributes.</p> +<div class="EXAMPLE"><a name="FFOAT" id="FFOAT"></a> +<p><b>Example 26. Form Attributes example</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <form.h> + +int main() +{ FIELD *field[3]; + FORM *my_form; + int ch; + + /* Initialize curses */ + initscr(); + start_color(); + cbreak(); + noecho(); + keypad(stdscr, TRUE); + + /* Initialize few color pairs */ + init_pair(1, COLOR_WHITE, COLOR_BLUE); + init_pair(2, COLOR_WHITE, COLOR_BLUE); + + /* Initialize the fields */ + field[0] = new_field(1, 10, 4, 18, 0, 0); + field[1] = new_field(1, 10, 6, 18, 0, 0); + field[2] = NULL; + + /* Set field options */ + set_field_fore(field[0], COLOR_PAIR(1));/* Put the field with blue background */ + set_field_back(field[0], COLOR_PAIR(2));/* and white foreground (characters */ + /* are printed in white */ + field_opts_off(field[0], O_AUTOSKIP); /* Don't go to next field when this */ + /* Field is filled up */ + set_field_back(field[1], A_UNDERLINE); + field_opts_off(field[1], O_AUTOSKIP); + + /* Create the form and post it */ + my_form = new_form(field); + post_form(my_form); + refresh(); + + set_current_field(my_form, field[0]); /* Set focus to the colored field */ + mvprintw(4, 10, "Value 1:"); + mvprintw(6, 10, "Value 2:"); + mvprintw(LINES - 2, 0, "Use UP, DOWN arrow keys to switch between fields"); + refresh(); + + /* Loop through to get user requests */ + while((ch = getch()) != KEY_F(1)) + { switch(ch) + { case KEY_DOWN: + /* Go to next field */ + form_driver(my_form, REQ_NEXT_FIELD); + /* Go to the end of the present buffer */ + /* Leaves nicely at the last character */ + form_driver(my_form, REQ_END_LINE); + break; + case KEY_UP: + /* Go to previous field */ + form_driver(my_form, REQ_PREV_FIELD); + form_driver(my_form, REQ_END_LINE); + break; + default: + /* If this is a normal character, it gets */ + /* Printed */ + form_driver(my_form, ch); + break; + } + } + + /* Un post form and free the memory */ + unpost_form(my_form); + free_form(my_form); + free_field(field[0]); + free_field(field[1]); + + endwin(); + return 0; +}</span></font> +</pre></td> +</tr> +</table> +</div> +<p>Play with the color pairs and try to understand the foreground +and background attributes. In my programs using color attributes, I +usually set only the background with set_field_back(). Curses +simply doesn't allow defining individual color attributes.</p> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="FIELDOPTIONBITS" id= +"FIELDOPTIONBITS">18.3.5. Field Option Bits</a></h4> +<p>There is also a large collection of field option bits you can +set to control various aspects of forms processing. You can +manipulate them with these functions:</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000">int set_field_opts(FIELD *field, /* field to alter */ + int attr); /* attribute to set */ + +int field_opts_on(FIELD *field, /* field to alter */ + int attr); /* attributes to turn on */ + +int field_opts_off(FIELD *field, /* field to alter */ + int attr); /* attributes to turn off */ + +int field_opts(FIELD *field); /* field to query */ </font> +</pre></td> +</tr> +</table> +<p>The function set_field_opts() can be used to directly set +attributes of a field or you can choose to switch a few attributes +on and off with field_opts_on() and field_opts_off() selectively. +Anytime you can query the attributes of a field with field_opts(). +The following is the list of available options. By default, all +options are on.</p> +<div class="VARIABLELIST"> +<dl> +<dt>O_VISIBLE</dt> +<dd> +<p>Controls whether the field is visible on the screen. Can be used +during form processing to hide or pop up fields depending on the +value of parent fields.</p> +</dd> +<dt>O_ACTIVE</dt> +<dd> +<p>Controls whether the field is active during forms processing +(i.e. visited by form navigation keys). Can be used to make labels +or derived fields with buffer values alterable by the forms +application, not the user.</p> +</dd> +<dt>O_PUBLIC</dt> +<dd> +<p>Controls whether data is displayed during field entry. If this +option is turned off on a field, the library will accept and edit +data in that field, but it will not be displayed and the visible +field cursor will not move. You can turn off the O_PUBLIC bit to +define password fields.</p> +</dd> +<dt>O_EDIT</dt> +<dd> +<p>Controls whether the field's data can be modified. When this +option is off, all editing requests except <var class= +"LITERAL">REQ_PREV_CHOICE</var> and <var class= +"LITERAL">REQ_NEXT_CHOICE</var>will fail. Such read-only fields may +be useful for help messages.</p> +</dd> +<dt>O_WRAP</dt> +<dd> +<p>Controls word-wrapping in multi-line fields. Normally, when any +character of a (blank-separated) word reaches the end of the +current line, the entire word is wrapped to the next line (assuming +there is one). When this option is off, the word will be split +across the line break.</p> +</dd> +<dt>O_BLANK</dt> +<dd> +<p>Controls field blanking. When this option is on, entering a +character at the first field position erases the entire field +(except for the just-entered character).</p> +</dd> +<dt>O_AUTOSKIP</dt> +<dd> +<p>Controls automatic skip to next field when this one fills. +Normally, when the forms user tries to type more data into a field +than will fit, the editing location jumps to next field. When this +option is off, the user's cursor will hang at the end of the field. +This option is ignored in dynamic fields that have not reached +their size limit.</p> +</dd> +<dt>O_NULLOK</dt> +<dd> +<p>Controls whether validation is applied to blank fields. +Normally, it is not; the user can leave a field blank without +invoking the usual validation check on exit. If this option is off +on a field, exit from it will invoke a validation check.</p> +</dd> +<dt>O_PASSOK</dt> +<dd> +<p>Controls whether validation occurs on every exit, or only after +the field is modified. Normally the latter is true. Setting +O_PASSOK may be useful if your field's validation function may +change during forms processing.</p> +</dd> +<dt>O_STATIC</dt> +<dd> +<p>Controls whether the field is fixed to its initial dimensions. +If you turn this off, the field becomes dynamic and will stretch to +fit entered data.</p> +</dd> +</dl> +</div> +<p>A field's options cannot be changed while the field is currently +selected. However, options may be changed on posted fields that are +not current.</p> +<p>The option values are bit-masks and can be composed with +logical-or in the obvious way. You have seen the usage of switching +off O_AUTOSKIP option. The following example clarifies usage of +some more options. Other options are explained where +appropriate.</p> +<div class="EXAMPLE"><a name="FFOOP" id="FFOOP"></a> +<p><b>Example 27. Field Options Usage example</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <form.h> + +#define STARTX 15 +#define STARTY 4 +#define WIDTH 25 + +#define N_FIELDS 3 + +int main() +{ FIELD *field[N_FIELDS]; + FORM *my_form; + int ch, i; + + /* Initialize curses */ + initscr(); + cbreak(); + noecho(); + keypad(stdscr, TRUE); + + /* Initialize the fields */ + for(i = 0; i < N_FIELDS - 1; ++i) + field[i] = new_field(1, WIDTH, STARTY + i * 2, STARTX, 0, 0); + field[N_FIELDS - 1] = NULL; + + /* Set field options */ + set_field_back(field[1], A_UNDERLINE); /* Print a line for the option */ + + field_opts_off(field[0], O_ACTIVE); /* This field is a static label */ + field_opts_off(field[1], O_PUBLIC); /* This filed is like a password field*/ + field_opts_off(field[1], O_AUTOSKIP); /* To avoid entering the same field */ + /* after last character is entered */ + + /* Create the form and post it */ + my_form = new_form(field); + post_form(my_form); + refresh(); + + set_field_just(field[0], JUSTIFY_CENTER); /* Center Justification */ + set_field_buffer(field[0], 0, "This is a static Field"); + /* Initialize the field */ + mvprintw(STARTY, STARTX - 10, "Field 1:"); + mvprintw(STARTY + 2, STARTX - 10, "Field 2:"); + refresh(); + + /* Loop through to get user requests */ + while((ch = getch()) != KEY_F(1)) + { switch(ch) + { case KEY_DOWN: + /* Go to next field */ + form_driver(my_form, REQ_NEXT_FIELD); + /* Go to the end of the present buffer */ + /* Leaves nicely at the last character */ + form_driver(my_form, REQ_END_LINE); + break; + case KEY_UP: + /* Go to previous field */ + form_driver(my_form, REQ_PREV_FIELD); + form_driver(my_form, REQ_END_LINE); + break; + default: + /* If this is a normal character, it gets */ + /* Printed */ + form_driver(my_form, ch); + break; + } + } + + /* Un post form and free the memory */ + unpost_form(my_form); + free_form(my_form); + free_field(field[0]); + free_field(field[1]); + + endwin(); + return 0; +}</span></font> +</pre></td> +</tr> +</table> +</div> +<p>This example, though useless, shows the usage of options. If +used properly, they can present information very effectively in a +form. The second field being not O_PUBLIC, does not show the +characters you are typing.</p> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="FIELDSTATUS" id="FIELDSTATUS">18.3.6. +Field Status</a></h4> +<p>The field status specifies whether the field has got edited or +not. It is initially set to FALSE and when user enters something +and the data buffer gets modified it becomes TRUE. So a field's +status can be queried to find out whether it has been modified or +not. The following functions can assist in those operations.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000">int set_field_status(FIELD *field, /* field to alter */ + int status); /* status to set */ + +int field_status(FIELD *field); /* fetch status of field */</font> +</pre></td> +</tr> +</table> +<p>It's better to check the field's status only after after leaving +the field, as data buffer might not have been updated yet as the +validation is still due. To guarantee that right status is +returned, call field_status() either (1) in the field's exit +validation check routine, (2) from the field's or form's +initialization or termination hooks, or (3) just after a +REQ_VALIDATION request has been processed by the forms driver</p> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="FIELDUSERPTR" id="FIELDUSERPTR">18.3.7. +Field User Pointer</a></h4> +<p>Every field structure contains one pointer that can be used by +the user for various purposes. It is not touched by forms library +and can be used for any purpose by the user. The following +functions set and fetch user pointer.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000">int set_field_userptr(FIELD *field, + char *userptr); /* the user pointer you wish to associate */ + /* with the field */ + +char *field_userptr(FIELD *field); /* fetch user pointer of the field */</font> +</pre></td> +</tr> +</table> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="VARIABLESIZEFIELDS" id= +"VARIABLESIZEFIELDS">18.3.8. Variable-Sized Fields</a></h4> +<p>If you want a dynamically changing field with variable width, +this is the feature you want to put to full use. This will allow +the user to enter more data than the original size of the field and +let the field grow. According to the field orientation it will +scroll horizontally or vertically to incorporate the new data.</p> +<p>To make a field dynamically growable, the option O_STATIC should +be turned off. This can be done with a</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000"> field_opts_off(field_pointer, O_STATIC);</font> +</pre></td> +</tr> +</table> +<p>But it's usually not advisable to allow a field to grow +infinitely. You can set a maximum limit to the growth of the field +with</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000">int set_max_field(FIELD *field, /* Field on which to operate */ + int max_growth); /* maximum growth allowed for the field */</font> +</pre></td> +</tr> +</table> +<p>The field info for a dynamically growable field can be retrieved +by</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000">int dynamic_field_info( FIELD *field, /* Field on which to operate */ + int *prows, /* number of rows will be filled in this */ + int *pcols, /* number of columns will be filled in this*/ + int *pmax) /* maximum allowable growth will be filled */ + /* in this */</font> +</pre></td> +</tr> +</table> +Though field_info work as usual, it is advisable to use this +function to get the proper attributes of a dynamically growable +field. +<p>Recall the library routine new_field; a new field created with +height set to one will be defined to be a one line field. A new +field created with height greater than one will be defined to be a +multi line field.</p> +<p>A one line field with O_STATIC turned off (dynamically growable +field) will contain a single fixed row, but the number of columns +can increase if the user enters more data than the initial field +will hold. The number of columns displayed will remain fixed and +the additional data will scroll horizontally.</p> +<p>A multi line field with O_STATIC turned off (dynamically +growable field) will contain a fixed number of columns, but the +number of rows can increase if the user enters more data than the +initial field will hold. The number of rows displayed will remain +fixed and the additional data will scroll vertically.</p> +<p>The above two paragraphs pretty much describe a dynamically +growable field's behavior. The way other parts of forms library +behaves is described below:</p> +<ol type="1"> +<li> +<p>The field option O_AUTOSKIP will be ignored if the option +O_STATIC is off and there is no maximum growth specified for the +field. Currently, O_AUTOSKIP generates an automatic REQ_NEXT_FIELD +form driver request when the user types in the last character +position of a field. On a growable field with no maximum growth +specified, there is no last character position. If a maximum growth +is specified, the O_AUTOSKIP option will work as normal if the +field has grown to its maximum size.</p> +</li> +<li> +<p>The field justification will be ignored if the option O_STATIC +is off. Currently, set_field_just can be used to JUSTIFY_LEFT, +JUSTIFY_RIGHT, JUSTIFY_CENTER the contents of a one line field. A +growable one line field will, by definition, grow and scroll +horizontally and may contain more data than can be justified. The +return from field_just will be unchanged.</p> +</li> +<li> +<p>The overloaded form driver request REQ_NEW_LINE will operate the +same way regardless of the O_NL_OVERLOAD form option if the field +option O_STATIC is off and there is no maximum growth specified for +the field. Currently, if the form option O_NL_OVERLOAD is on, +REQ_NEW_LINE implicitly generates a REQ_NEXT_FIELD if called from +the last line of a field. If a field can grow without bound, there +is no last line, so REQ_NEW_LINE will never implicitly generate a +REQ_NEXT_FIELD. If a maximum growth limit is specified and the +O_NL_OVERLOAD form option is on, REQ_NEW_LINE will only implicitly +generate REQ_NEXT_FIELD if the field has grown to its maximum size +and the user is on the last line.</p> +</li> +<li> +<p>The library call dup_field will work as usual; it will duplicate +the field, including the current buffer size and contents of the +field being duplicated. Any specified maximum growth will also be +duplicated.</p> +</li> +<li> +<p>The library call link_field will work as usual; it will +duplicate all field attributes and share buffers with the field +being linked. If the O_STATIC field option is subsequently changed +by a field sharing buffers, how the system reacts to an attempt to +enter more data into the field than the buffer will currently hold +will depend on the setting of the option in the current field.</p> +</li> +<li> +<p>The library call field_info will work as usual; the variable +nrow will contain the value of the original call to new_field. The +user should use dynamic_field_info, described above, to query the +current size of the buffer.</p> +</li> +</ol> +<p>Some of the above points make sense only after explaining form +driver. We will be looking into that in next few sections.</p> +</div> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="FORMWINDOWS" id="FORMWINDOWS">18.4. Form +Windows</a></h3> +<p>The form windows concept is pretty much similar to menu windows. +Every form is associated with a main window and a sub window. The +form main window displays any title or border associated or +whatever the user wishes. Then the sub window contains all the +fields and displays them according to their position. This gives +the flexibility of manipulating fancy form displaying very +easily.</p> +<p>Since this is pretty much similar to menu windows, I am +providing an example with out much explanation. The functions are +similar and they work the same way.</p> +<div class="EXAMPLE"><a name="FFOWI" id="FFOWI"></a> +<p><b>Example 28. Form Windows Example</b></p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000"><span class= +"INLINEMEDIAOBJECT">#include <form.h> + +void print_in_middle(WINDOW *win, int starty, int startx, int width, char *string, chtype color); + +int main() +{ + FIELD *field[3]; + FORM *my_form; + WINDOW *my_form_win; + int ch, rows, cols; + + /* Initialize curses */ + initscr(); + start_color(); + cbreak(); + noecho(); + keypad(stdscr, TRUE); + + /* Initialize few color pairs */ + init_pair(1, COLOR_RED, COLOR_BLACK); + + /* Initialize the fields */ + field[0] = new_field(1, 10, 6, 1, 0, 0); + field[1] = new_field(1, 10, 8, 1, 0, 0); + field[2] = NULL; + + /* Set field options */ + set_field_back(field[0], A_UNDERLINE); + field_opts_off(field[0], O_AUTOSKIP); /* Don't go to next field when this */ + /* Field is filled up */ + set_field_back(field[1], A_UNDERLINE); + field_opts_off(field[1], O_AUTOSKIP); + + /* Create the form and post it */ + my_form = new_form(field); + + /* Calculate the area required for the form */ + scale_form(my_form, &rows, &cols); + + /* Create the window to be associated with the form */ + my_form_win = newwin(rows + 4, cols + 4, 4, 4); + keypad(my_form_win, TRUE); + + /* Set main window and sub window */ + set_form_win(my_form, my_form_win); + set_form_sub(my_form, derwin(my_form_win, rows, cols, 2, 2)); + + /* Print a border around the main window and print a title */ + box(my_form_win, 0, 0); + print_in_middle(my_form_win, 1, 0, cols + 4, "My Form", COLOR_PAIR(1)); + + post_form(my_form); + wrefresh(my_form_win); + + mvprintw(LINES - 2, 0, "Use UP, DOWN arrow keys to switch between fields"); + refresh(); + + /* Loop through to get user requests */ + while((ch = wgetch(my_form_win)) != KEY_F(1)) + { switch(ch) + { case KEY_DOWN: + /* Go to next field */ + form_driver(my_form, REQ_NEXT_FIELD); + /* Go to the end of the present buffer */ + /* Leaves nicely at the last character */ + form_driver(my_form, REQ_END_LINE); + break; + case KEY_UP: + /* Go to previous field */ + form_driver(my_form, REQ_PREV_FIELD); + form_driver(my_form, REQ_END_LINE); + break; + default: + /* If this is a normal character, it gets */ + /* Printed */ + form_driver(my_form, ch); + break; + } + } + + /* Un post form and free the memory */ + unpost_form(my_form); + free_form(my_form); + free_field(field[0]); + free_field(field[1]); + + endwin(); + return 0; +} + +void print_in_middle(WINDOW *win, int starty, int startx, int width, char *string, chtype color) +{ int length, x, y; + float temp; + + if(win == NULL) + win = stdscr; + getyx(win, y, x); + if(startx != 0) + x = startx; + if(starty != 0) + y = starty; + if(width == 0) + width = 80; + + length = strlen(string); + temp = (width - length)/ 2; + x = startx + (int)temp; + wattron(win, color); + mvwprintw(win, y, x, "%s", string); + wattroff(win, color); + refresh(); +}</span></font> +</pre></td> +</tr> +</table> +</div> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="FILEDVALIDATE" id="FILEDVALIDATE">18.5. +Field Validation</a></h3> +<p>By default, a field will accept any data input by the user. It +is possible to attach validation to the field. Then any attempt by +the user to leave the field, while it contains data that doesn't +match the validation type will fail. Some validation types also +have a character-validity check for each time a character is +entered in the field.</p> +<p>Validation can be attached to a field with the following +function.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000">int set_field_type(FIELD *field, /* field to alter */ + FIELDTYPE *ftype, /* type to associate */ + ...); /* additional arguments*/</font> +</pre></td> +</tr> +</table> +Once set, the validation type for a field can be queried with +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000">FIELDTYPE *field_type(FIELD *field); /* field to query */</font> +</pre></td> +</tr> +</table> +<p>The form driver validates the data in a field only when data is +entered by the end-user. Validation does not occur when</p> +<ul> +<li> +<p>the application program changes the field value by calling +set_field_buffer.</p> +</li> +<li> +<p>linked field values are changed indirectly -- by changing the +field to which they are linked</p> +</li> +</ul> +<p>The following are the pre-defined validation types. You can also +specify custom validation, though it's a bit tricky and +cumbersome.</p> +<h1 class="BRIDGEHEAD"><a name="AEN1069" id= +"AEN1069"></a>TYPE_ALPHA</h1> +<p>This field type accepts alphabetic data; no blanks, no digits, +no special characters (this is checked at character-entry time). It +is set up with:</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000">int set_field_type(FIELD *field, /* field to alter */ + TYPE_ALPHA, /* type to associate */ + int width); /* maximum width of field */</font> +</pre></td> +</tr> +</table> +<p>The width argument sets a minimum width of data. The user has to +enter at-least width number of characters before he can leave the +field. Typically you'll want to set this to the field width; if +it's greater than the field width, the validation check will always +fail. A minimum width of zero makes field completion optional.</p> +<h1 class="BRIDGEHEAD"><a name="AEN1073" id= +"AEN1073"></a>TYPE_ALNUM</h1> +<p>This field type accepts alphabetic data and digits; no blanks, +no special characters (this is checked at character-entry time). It +is set up with:</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000">int set_field_type(FIELD *field, /* field to alter */ + TYPE_ALNUM, /* type to associate */ + int width); /* maximum width of field */</font> +</pre></td> +</tr> +</table> +<p>The width argument sets a minimum width of data. As with +TYPE_ALPHA, typically you'll want to set this to the field width; +if it's greater than the field width, the validation check will +always fail. A minimum width of zero makes field completion +optional.</p> +<h1 class="BRIDGEHEAD"><a name="AEN1077" id= +"AEN1077"></a>TYPE_ENUM</h1> +<p>This type allows you to restrict a field's values to be among a +specified set of string values (for example, the two-letter postal +codes for U.S. states). It is set up with:</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000">int set_field_type(FIELD *field, /* field to alter */ + TYPE_ENUM, /* type to associate */ + char **valuelist; /* list of possible values */ + int checkcase; /* case-sensitive? */ + int checkunique); /* must specify uniquely? */</font> +</pre></td> +</tr> +</table> +<p>The valuelist parameter must point at a NULL-terminated list of +valid strings. The checkcase argument, if true, makes comparison +with the string case-sensitive.</p> +<p>When the user exits a TYPE_ENUM field, the validation procedure +tries to complete the data in the buffer to a valid entry. If a +complete choice string has been entered, it is of course valid. But +it is also possible to enter a prefix of a valid string and have it +completed for you.</p> +<p>By default, if you enter such a prefix and it matches more than +one value in the string list, the prefix will be completed to the +first matching value. But the checkunique argument, if true, +requires prefix matches to be unique in order to be valid.</p> +<p>The REQ_NEXT_CHOICE and REQ_PREV_CHOICE input requests can be +particularly useful with these fields.</p> +<h1 class="BRIDGEHEAD"><a name="AEN1084" id= +"AEN1084"></a>TYPE_INTEGER</h1> +<p>This field type accepts an integer. It is set up as follows:</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000">int set_field_type(FIELD *field, /* field to alter */ + TYPE_INTEGER, /* type to associate */ + int padding, /* # places to zero-pad to */ + int vmin, int vmax); /* valid range */</font> +</pre></td> +</tr> +</table> +<p>Valid characters consist of an optional leading minus and +digits. The range check is performed on exit. If the range maximum +is less than or equal to the minimum, the range is ignored.</p> +<p>If the value passes its range check, it is padded with as many +leading zero digits as necessary to meet the padding argument.</p> +<p>A TYPE_INTEGER value buffer can conveniently be interpreted with +the C library function atoi(3).</p> +<h1 class="BRIDGEHEAD"><a name="AEN1090" id= +"AEN1090"></a>TYPE_NUMERIC</h1> +<p>This field type accepts a decimal number. It is set up as +follows:</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000">int set_field_type(FIELD *field, /* field to alter */ + TYPE_NUMERIC, /* type to associate */ + int padding, /* # places of precision */ + int vmin, int vmax); /* valid range */</font> +</pre></td> +</tr> +</table> +<p>Valid characters consist of an optional leading minus and +digits. possibly including a decimal point. The range check is +performed on exit. If the range maximum is less than or equal to +the minimum, the range is ignored.</p> +<p>If the value passes its range check, it is padded with as many +trailing zero digits as necessary to meet the padding argument.</p> +<p>A TYPE_NUMERIC value buffer can conveniently be interpreted with +the C library function atof(3).</p> +<h1 class="BRIDGEHEAD"><a name="AEN1096" id= +"AEN1096"></a>TYPE_REGEXP</h1> +<p>This field type accepts data matching a regular expression. It +is set up as follows:</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000">int set_field_type(FIELD *field, /* field to alter */ + TYPE_REGEXP, /* type to associate */ + char *regexp); /* expression to match */</font> +</pre></td> +</tr> +</table> +<p>The syntax for regular expressions is that of regcomp(3). The +check for regular-expression match is performed on exit.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="FORMDRIVER" id="FORMDRIVER">18.6. Form +Driver: The work horse of the forms system</a></h3> +<p>As in the menu system, form_driver() plays a very important role +in forms system. All types of requests to forms system should be +funneled through form_driver().</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000">int form_driver(FORM *form, /* form on which to operate */ + int request) /* form request code */</font> +</pre></td> +</tr> +</table> +<p>As you have seen some of the examples above, you have to be in a +loop looking for user input and then decide whether it's a field +data or a form request. The form requests are then passed to +form_driver() to do the work.</p> +<p>The requests roughly can be divided into following categories. +Different requests and their usage is explained below:</p> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="PAGENAVREQ" id="PAGENAVREQ">18.6.1. Page +Navigation Requests</a></h4> +<p>These requests cause page-level moves through the form, +triggering display of a new form screen. A form can be made of +multiple pages. If you have a big form with lot of fields and +logical sections, then you can divide the form into pages. The +function set_new_page() to set a new page at the field +specified.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000">int set_new_page(FIELD *field,/* Field at which page break to be set or unset */ + bool new_page_flag); /* should be TRUE to put a break */</font> +</pre></td> +</tr> +</table> +<p>The following requests allow you to move to different pages</p> +<ul> +<li> +<p><em>REQ_NEXT_PAGE</em> Move to the next form page.</p> +</li> +<li> +<p><em>REQ_PREV_PAGE</em> Move to the previous form page.</p> +</li> +<li> +<p><em>REQ_FIRST_PAGE</em> Move to the first form page.</p> +</li> +<li> +<p><em>REQ_LAST_PAGE</em> Move to the last form page.</p> +</li> +</ul> +<p>These requests treat the list as cyclic; that is, REQ_NEXT_PAGE +from the last page goes to the first, and REQ_PREV_PAGE from the +first page goes to the last.</p> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="INTERFIELDNAVREQ" id= +"INTERFIELDNAVREQ">18.6.2. Inter-Field Navigation Requests</a></h4> +<p>These requests handle navigation between fields on the same +page.</p> +<ul> +<li> +<p><em>REQ_NEXT_FIELD</em> Move to next field.</p> +</li> +<li> +<p><em>REQ_PREV_FIELD</em> Move to previous field.</p> +</li> +<li> +<p><em>REQ_FIRST_FIELD</em> Move to the first field.</p> +</li> +<li> +<p><em>REQ_LAST_FIELD</em> Move to the last field.</p> +</li> +<li> +<p><em>REQ_SNEXT_FIELD</em> Move to sorted next field.</p> +</li> +<li> +<p><em>REQ_SPREV_FIELD</em> Move to sorted previous field.</p> +</li> +<li> +<p><em>REQ_SFIRST_FIELD</em> Move to the sorted first field.</p> +</li> +<li> +<p><em>REQ_SLAST_FIELD</em> Move to the sorted last field.</p> +</li> +<li> +<p><em>REQ_LEFT_FIELD</em> Move left to field.</p> +</li> +<li> +<p><em>REQ_RIGHT_FIELD</em> Move right to field.</p> +</li> +<li> +<p><em>REQ_UP_FIELD</em> Move up to field.</p> +</li> +<li> +<p><em>REQ_DOWN_FIELD</em> Move down to field.</p> +</li> +</ul> +<p>These requests treat the list of fields on a page as cyclic; +that is, REQ_NEXT_FIELD from the last field goes to the first, and +REQ_PREV_FIELD from the first field goes to the last. The order of +the fields for these (and the REQ_FIRST_FIELD and REQ_LAST_FIELD +requests) is simply the order of the field pointers in the form +array (as set up by new_form() or set_form_fields()</p> +<p>It is also possible to traverse the fields as if they had been +sorted in screen-position order, so the sequence goes left-to-right +and top-to-bottom. To do this, use the second group of four +sorted-movement requests.</p> +<p>Finally, it is possible to move between fields using visual +directions up, down, right, and left. To accomplish this, use the +third group of four requests. Note, however, that the position of a +form for purposes of these requests is its upper-left corner.</p> +<p>For example, suppose you have a multi-line field B, and two +single-line fields A and C on the same line with B, with A to the +left of B and C to the right of B. A REQ_MOVE_RIGHT from A will go +to B only if A, B, and C all share the same first line; otherwise +it will skip over B to C.</p> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="INTRAFIELDNAVREQ" id= +"INTRAFIELDNAVREQ">18.6.3. Intra-Field Navigation Requests</a></h4> +<p>These requests drive movement of the edit cursor within the +currently selected field.</p> +<ul> +<li> +<p><em>REQ_NEXT_CHAR</em> Move to next character.</p> +</li> +<li> +<p><em>REQ_PREV_CHAR</em> Move to previous character.</p> +</li> +<li> +<p><em>REQ_NEXT_LINE</em> Move to next line.</p> +</li> +<li> +<p><em>REQ_PREV_LINE</em> Move to previous line.</p> +</li> +<li> +<p><em>REQ_NEXT_WORD</em> Move to next word.</p> +</li> +<li> +<p><em>REQ_PREV_WORD</em> Move to previous word.</p> +</li> +<li> +<p><em>REQ_BEG_FIELD</em> Move to beginning of field.</p> +</li> +<li> +<p><em>REQ_END_FIELD</em> Move to end of field.</p> +</li> +<li> +<p><em>REQ_BEG_LINE</em> Move to beginning of line.</p> +</li> +<li> +<p><em>REQ_END_LINE</em> Move to end of line.</p> +</li> +<li> +<p><em>REQ_LEFT_CHAR</em> Move left in field.</p> +</li> +<li> +<p><em>REQ_RIGHT_CHAR</em> Move right in field.</p> +</li> +<li> +<p><em>REQ_UP_CHAR</em> Move up in field.</p> +</li> +<li> +<p><em>REQ_DOWN_CHAR</em> Move down in field.</p> +</li> +</ul> +<p>Each word is separated from the previous and next characters by +whitespace. The commands to move to beginning and end of line or +field look for the first or last non-pad character in their +ranges.</p> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="SCROLLREQ" id="SCROLLREQ">18.6.4. +Scrolling Requests</a></h4> +<p>Fields that are dynamic and have grown and fields explicitly +created with offscreen rows are scrollable. One-line fields scroll +horizontally; multi-line fields scroll vertically. Most scrolling +is triggered by editing and intra-field movement (the library +scrolls the field to keep the cursor visible). It is possible to +explicitly request scrolling with the following requests:</p> +<ul> +<li> +<p><em>REQ_SCR_FLINE</em> Scroll vertically forward a line.</p> +</li> +<li> +<p><em>REQ_SCR_BLINE</em> Scroll vertically backward a line.</p> +</li> +<li> +<p><em>REQ_SCR_FPAGE</em> Scroll vertically forward a page.</p> +</li> +<li> +<p><em>REQ_SCR_BPAGE</em> Scroll vertically backward a page.</p> +</li> +<li> +<p><em>REQ_SCR_FHPAGE</em> Scroll vertically forward half a +page.</p> +</li> +<li> +<p><em>REQ_SCR_BHPAGE</em> Scroll vertically backward half a +page.</p> +</li> +<li> +<p><em>REQ_SCR_FCHAR</em> Scroll horizontally forward a +character.</p> +</li> +<li> +<p><em>REQ_SCR_BCHAR</em> Scroll horizontally backward a +character.</p> +</li> +<li> +<p><em>REQ_SCR_HFLINE</em> Scroll horizontally one field width +forward.</p> +</li> +<li> +<p><em>REQ_SCR_HBLINE</em> Scroll horizontally one field width +backward.</p> +</li> +<li> +<p><em>REQ_SCR_HFHALF</em> Scroll horizontally one half field width +forward.</p> +</li> +<li> +<p><em>REQ_SCR_HBHALF</em> Scroll horizontally one half field width +backward.</p> +</li> +</ul> +<p>For scrolling purposes, a page of a field is the height of its +visible part.</p> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="EDITREQ" id="EDITREQ">18.6.5. Editing +Requests</a></h4> +<p>When you pass the forms driver an ASCII character, it is treated +as a request to add the character to the field's data buffer. +Whether this is an insertion or a replacement depends on the +field's edit mode (insertion is the default.</p> +<p>The following requests support editing the field and changing +the edit mode:</p> +<ul> +<li> +<p><em>REQ_INS_MODE</em> Set insertion mode.</p> +</li> +<li> +<p><em>REQ_OVL_MODE</em> Set overlay mode.</p> +</li> +<li> +<p><em>REQ_NEW_LINE</em> New line request (see below for +explanation).</p> +</li> +<li> +<p><em>REQ_INS_CHAR</em> Insert space at character location.</p> +</li> +<li> +<p><em>REQ_INS_LINE</em> Insert blank line at character +location.</p> +</li> +<li> +<p><em>REQ_DEL_CHAR</em> Delete character at cursor.</p> +</li> +<li> +<p><em>REQ_DEL_PREV</em> Delete previous word at cursor.</p> +</li> +<li> +<p><em>REQ_DEL_LINE</em> Delete line at cursor.</p> +</li> +<li> +<p><em>REQ_DEL_WORD</em> Delete word at cursor.</p> +</li> +<li> +<p><em>REQ_CLR_EOL</em> Clear to end of line.</p> +</li> +<li> +<p><em>REQ_CLR_EOF</em> Clear to end of field.</p> +</li> +<li> +<p><em>REQ_CLR_FIELD</em> Clear entire field.</p> +</li> +</ul> +<p>The behavior of the REQ_NEW_LINE and REQ_DEL_PREV requests is +complicated and partly controlled by a pair of forms options. The +special cases are triggered when the cursor is at the beginning of +a field, or on the last line of the field.</p> +<p>First, we consider REQ_NEW_LINE:</p> +<p>The normal behavior of REQ_NEW_LINE in insert mode is to break +the current line at the position of the edit cursor, inserting the +portion of the current line after the cursor as a new line +following the current and moving the cursor to the beginning of +that new line (you may think of this as inserting a newline in the +field buffer).</p> +<p>The normal behavior of REQ_NEW_LINE in overlay mode is to clear +the current line from the position of the edit cursor to end of +line. The cursor is then moved to the beginning of the next +line.</p> +<p>However, REQ_NEW_LINE at the beginning of a field, or on the +last line of a field, instead does a REQ_NEXT_FIELD. O_NL_OVERLOAD +option is off, this special action is disabled.</p> +<p>Now, let us consider REQ_DEL_PREV:</p> +<p>The normal behavior of REQ_DEL_PREV is to delete the previous +character. If insert mode is on, and the cursor is at the start of +a line, and the text on that line will fit on the previous one, it +instead appends the contents of the current line to the previous +one and deletes the current line (you may think of this as deleting +a newline from the field buffer).</p> +<p>However, REQ_DEL_PREV at the beginning of a field is instead +treated as a REQ_PREV_FIELD.</p> +<p>If the O_BS_OVERLOAD option is off, this special action is +disabled and the forms driver just returns E_REQUEST_DENIED.</p> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="ORDERREQ" id="ORDERREQ">18.6.6. Order +Requests</a></h4> +<p>If the type of your field is ordered, and has associated +functions for getting the next and previous values of the type from +a given value, there are requests that can fetch that value into +the field buffer:</p> +<ul> +<li> +<p><em>REQ_NEXT_CHOICE</em> Place the successor value of the +current value in the buffer.</p> +</li> +<li> +<p><em>REQ_PREV_CHOICE</em> Place the predecessor value of the +current value in the buffer.</p> +</li> +</ul> +<p>Of the built-in field types, only TYPE_ENUM has built-in +successor and predecessor functions. When you define a field type +of your own (see Custom Validation Types), you can associate our +own ordering functions.</p> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="APPLICCOMMANDS" id= +"APPLICCOMMANDS">18.6.7. Application Commands</a></h4> +<p>Form requests are represented as integers above the curses value +greater than KEY_MAX and less than or equal to the constant +MAX_COMMAND. A value within this range gets ignored by +form_driver(). So this can be used for any purpose by the +application. It can be treated as an application specific action +and take corresponding action.</p> +</div> +</div> +</div> +<div class="SECT1"> +<hr> +<h2 class="SECT1"><a name="TOOLS" id="TOOLS">19. Tools and Widget +Libraries</a></h2> +<p>Now that you have seen the capabilities of ncurses and its +sister libraries, you are rolling your sleeves up and gearing for a +project that heavily manipulates screen. But wait.. It can be +pretty difficult to write and maintain complex GUI widgets in plain +ncurses or even with the additional libraries. There are some +ready-to-use tools and widget libraries that can be used instead of +writing your own widgets. You can use some of them, get ideas from +the code, or even extend them.</p> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="CDK" id="CDK">19.1. CDK (Curses +Development Kit)</a></h3> +<p>In the author's words</p> +<p><em>CDK stands for 'Curses Development Kit' and it currently +contains 21 ready to use widgets which facilitate the speedy +development of full screen curses programs.</em></p> +<p>The kit provides some useful widgets, which can be used in your +programs directly. It's pretty well written and the documentation +is very good. The examples in the examples directory can be a good +place to start for beginners. The CDK can be downloaded from +<a href="http://invisible-island.net/cdk/" target= +"_top">http://invisible-island.net/cdk/</a> . Follow the +instructions in README file to install it.</p> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="WIDGETLIST" id="WIDGETLIST">19.1.1. +Widget List</a></h4> +<p>The following is the list of widgets provided with cdk and their +description.</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color="#000000">Widget Type Quick Description +=========================================================================== +Alphalist Allows a user to select from a list of words, with + the ability to narrow the search list by typing in a + few characters of the desired word. +Buttonbox This creates a multiple button widget. +Calendar Creates a little simple calendar widget. +Dialog Prompts the user with a message, and the user + can pick an answer from the buttons provided. +Entry Allows the user to enter various types of information. +File Selector A file selector built from Cdk base widgets. This + example shows how to create more complicated widgets + using the Cdk widget library. +Graph Draws a graph. +Histogram Draws a histogram. +Item List Creates a pop up field which allows the user to select + one of several choices in a small field. Very useful + for things like days of the week or month names. +Label Displays messages in a pop up box, or the label can be + considered part of the screen. +Marquee Displays a message in a scrolling marquee. +Matrix Creates a complex matrix with lots of options. +Menu Creates a pull-down menu interface. +Multiple Line Entry A multiple line entry field. Very useful + for long fields. (like a description + field) +Radio List Creates a radio button list. +Scale Creates a numeric scale. Used for allowing a user to + pick a numeric value and restrict them to a range of + values. +Scrolling List Creates a scrolling list/menu list. +Scrolling Window Creates a scrolling log file viewer. Can add + information into the window while its running. + A good widget for displaying the progress of + something. (akin to a console window) +Selection List Creates a multiple option selection list. +Slider Akin to the scale widget, this widget provides a + visual slide bar to represent the numeric value. +Template Creates a entry field with character sensitive + positions. Used for pre-formatted fields like + dates and phone numbers. +Viewer This is a file/information viewer. Very useful + when you need to display loads of information. +===========================================================================</font> +</pre></td> +</tr> +</table> +<p>A few of the widgets are modified by Thomas Dickey in recent +versions.</p> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="CDKATTRACT" id="CDKATTRACT">19.1.2. Some +Attractive Features</a></h4> +<p>Apart from making our life easier with readily usable widgets, +cdk solves one frustrating problem with printing multi colored +strings, justified strings elegantly. Special formatting tags can +be embedded in the strings which are passed to CDK functions. For +Example</p> +<p>If the string</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000">"</B/1>This line should have a yellow foreground and a blue +background.<!1>"</font> +</pre></td> +</tr> +</table> +<p>given as a parameter to newCDKLabel(), it prints the line with +yellow foreground and blue background. There are other tags +available for justifying string, embedding special drawing +characters etc.. Please refer to the man page cdk_display(3X) for +details. The man page explains the usage with nice examples.</p> +</div> +<div class="SECT3"> +<hr> +<h4 class="SECT3"><a name="CDKCONCLUSION" id= +"CDKCONCLUSION">19.1.3. Conclusion</a></h4> +<p>All in all, CDK is a well-written package of widgets, which if +used properly can form a strong frame work for developing complex +GUI.</p> +</div> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="DIALOG" id="DIALOG">19.2. The +dialog</a></h3> +<p>Long long ago, in September 1994, when few people knew linux, +Jeff Tranter wrote an <a href= +"http://www2.linuxjournal.com/lj-issues/issue5/2807.html" target= +"_top">article</a> on dialog in Linux Journal. He starts the +article with these words..</p> +<p><em>Linux is based on the Unix operating system, but also +features a number of unique and useful kernel features and +application programs that often go beyond what is available under +Unix. One little-known gem is "dialog", a utility for creating +professional-looking dialog boxes from within shell scripts. This +article presents a tutorial introduction to the dialog utility, and +shows examples of how and where it can be used</em></p> +<p>As he explains, dialog is a real gem in making +professional-looking dialog boxes with ease. It creates a variety +of dialog boxes, menus, check lists etc.. It is usually installed +by default. If not, you can download it from <a href= +"http://invisible-island.net/dialog/" target="_top">Thomas +Dickey</a>'s site.</p> +<p>The above-mentioned article gives a very good overview of its +uses and capabilites. The man page has more details. It can be used +in variety of situations. One good example is building of linux +kernel in text mode. Linux kernel uses a modified version of dialog +tailored for its needs.</p> +<p>dialog was initially designed to be used with shell scripts. If +you want to use its functionality in a c program, then you can use +libdialog. The documentation regarding this is sparse. Definitive +reference is the dialog.h header file which comes with the library. +You may need to hack here and there to get the required output. The +source is easily customizable. I have used it on a number of +occasions by modifying the code.</p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="PERLCURSES" id="PERLCURSES">19.3. Perl +Curses Modules CURSES::FORM and CURSES::WIDGETS</a></h3> +<p>The perl module Curses, Curses::Form and Curses::Widgets give +access to curses from perl. If you have curses and basic perl is +installed, you can get these modules from <a href= +"http://www.cpan.org/modules/01modules.index.html" target= +"_top">CPAN All Modules page</a>. Get the three zipped modules in +the Curses category. Once installed you can use these modules from +perl scripts like any other module. For more information on perl +modules see perlmod man page. The above modules come with good +documentation and they have some demo scripts to test the +functionality. Though the widgets provided are very rudimentary, +these modules provide good access to curses library from perl.</p> +<p>Some of my code examples are converted to perl by Anuradha +Ratnaweera and they are available in the <var class= +"LITERAL">perl</var> directory.</p> +<p>For more information see man pages Curses(3) , Curses::Form(3) +and Curses::Widgets(3). These pages are installed only when the +above modules are acquired and installed.</p> +</div> +</div> +<div class="SECT1"> +<hr> +<h2 class="SECT1"><a name="JUSTFORFUN" id="JUSTFORFUN">20. Just For +Fun !!!</a></h2> +<p>This section contains few programs written by me just for fun. +They don't signify a better programming practice or the best way of +using ncurses. They are provided here so as to allow beginners to +get ideas and add more programs to this section. If you have +written a couple of nice, simple programs in curses and want them +to included here, contact <a href="mailto:ppadala@gmail.com" +target="_top">me</a>.</p> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="GAMEOFLIFE" id="GAMEOFLIFE">20.1. The +Game of Life</a></h3> +<p>Game of life is a wonder of math. In <a href= +"http://www.math.com/students/wonders/life/life.html" target= +"_top">Paul Callahan</a>'s words</p> +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="PROGRAMLISTING"> +<font color= +"#000000"><em>The Game of Life (or simply Life) is not a game in the conventional sense. There +are no players, and no winning or losing. Once the "pieces" are placed in the +starting position, the rules determine everything that happens later. +Nevertheless, Life is full of surprises! In most cases, it is impossible to look +at a starting position (or pattern) and see what will happen in the future. The +only way to find out is to follow the rules of the game.</em></font> +</pre></td> +</tr> +</table> +<p>This program starts with a simple inverted U pattern and shows +how wonderful life works. There is a lot of room for improvement in +the program. You can let the user enter pattern of his choice or +even take input from a file. You can also change rules and play +with a lot of variations. Search on <a href="http://www.google.com" +target="_top">google</a> for interesting information on game of +life.</p> +<p><em>File Path: JustForFun/life.c</em></p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="MAGIC" id="MAGIC">20.2. Magic +Square</a></h3> +<p>Magic Square, another wonder of math, is very simple to +understand but very difficult to make. In a magic square sum of the +numbers in each row, each column is equal. Even diagnol sum can be +equal. There are many variations which have special properties.</p> +<p>This program creates a simple magic square of odd order.</p> +<p><em>File Path: JustForFun/magic.c</em></p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="HANOI" id="HANOI">20.3. Towers of +Hanoi</a></h3> +<p>The famous towers of hanoi solver. The aim of the game is to +move the disks on the first peg to last peg, using middle peg as a +temporary stay. The catch is not to place a larger disk over a +small disk at any time.</p> +<p><em>File Path: JustForFun/hanoi.c</em></p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="QUEENS" id="QUEENS">20.4. Queens +Puzzle</a></h3> +<p>The objective of the famous N-Queen puzzle is to put N queens on +a N X N chess board without attacking each other.</p> +<p>This program solves it with a simple backtracking technique.</p> +<p><em>File Path: JustForFun/queens.c</em></p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="SHUFFLE" id="SHUFFLE">20.5. +Shuffle</a></h3> +<p>A fun game, if you have time to kill.</p> +<p><em>File Path: JustForFun/shuffle.c</em></p> +</div> +<div class="SECT2"> +<hr> +<h3 class="SECT2"><a name="TT" id="TT">20.6. Typing Tutor</a></h3> +<p>A simple typing tutor, I created more out of need than for ease +of use. If you know how to put your fingers correctly on the +keyboard, but lack practice, this can be helpful.</p> +<p><em>File Path: JustForFun/tt.c</em></p> +</div> +</div> +<div class="SECT1"> +<hr> +<h2 class="SECT1"><a name="REF" id="REF">21. References</a></h2> +<ul> +<li> +<p>NCURSES man pages</p> +</li> +<li> +<p>NCURSES FAQ at <a href= +"http://invisible-island.net/ncurses/ncurses.faq.html" target= +"_top">http://invisible-island.net/ncurses/ncurses.faq.html</a></p> +</li> +<li> +<p>Writing programs with NCURSES by Eric Raymond and Zeyd M. +Ben-Halim at <a href= +"http://invisible-island.net/ncurses/ncurses-intro.html" target= +"_top">http://invisible-island.net/ncurses/ncurses-intro.html</a> - +somewhat obsolete. I was inspired by this document and the +structure of this HOWTO follows from the original document</p> +</li> +</ul> +</div> +</div> +</body> +</html> diff --git a/contrib/ncurses/doc/html/announce.html b/contrib/ncurses/doc/html/announce.html index 3005e49d..f9dae07 100644 --- a/contrib/ncurses/doc/html/announce.html +++ b/contrib/ncurses/doc/html/announce.html @@ -1,15 +1,43 @@ <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 3.0//EN"> <!-- - $Id: announce.html,v 1.39 2000/10/20 10:47:16 tom Exp $ + $Id: announce.html,v 1.51 2006/12/17 23:32:42 tom Exp $ + **************************************************************************** + * Copyright (c) 1998-2005,2006 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. * + **************************************************************************** --> <HTML> <HEAD> -<TITLE>Announcing ncurses 5.2</TITLE> +<TITLE>Announcing ncurses 5.6</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>Announcing ncurses 5.2</H1> +<H1>Announcing ncurses 5.6</H1> The ncurses (new curses) library is a free software emulation of curses in System V Release 4.0, and more. It uses terminfo format, @@ -18,12 +46,15 @@ and multiple highlights and forms characters and function-key mapping, and has all the other SYSV-curses enhancements over BSD curses.<P> In mid-June 1995, the maintainer of 4.4BSD curses declared that he -considered 4.4BSD curses obsolete, and is encouraging the keepers of -Unix releases such as BSD/OS, freeBSD and netBSD to switch over to +considered 4.4BSD curses obsolete, and encouraged the keepers of +Unix releases such as BSD/OS, FreeBSD and NetBSD to switch over to ncurses.<P> -The ncurses code was developed under GNU/Linux. It should port easily to -any ANSI/POSIX-conforming UNIX. It has even been ported to OS/2 Warp!<P> +The ncurses code was developed under GNU/Linux. +It has been in use for some time with OpenBSD as the system curses library, +and on FreeBSD and NetBSD as an external package. +It should port easily to any ANSI/POSIX-conforming UNIX. +It has even been ported to OS/2 Warp!<P> The distribution includes the library and support utilities, including a terminfo compiler tic(1), a decompiler infocmp(1), clear(1), tput(1), tset(1), @@ -32,333 +63,305 @@ the library and tools.<P> The ncurses distribution is available via anonymous FTP at the GNU distribution site -<A HREF="ftp://ftp.gnu.org/pub/gnu/ncurses">ftp://ftp.gnu.org/pub/gnu/ncurses</A>. +<A HREF="ftp://ftp.gnu.org/gnu/ncurses/">ftp://ftp.gnu.org/gnu/ncurses/</A> . <br>It is also available at -<A HREF="ftp://dickey.his.com/ncurses">ftp://dickey.his.com/ncurses</A>. +<A HREF="ftp://invisible-island.net/ncurses/">ftp://invisible-island.net/ncurses/</A> . <H1>Release Notes</H1> -This release is designed to be upward compatible from ncurses 5.0 and 5.1; +This release is designed to be upward compatible from ncurses 5.0 through 5.5; very few applications will require recompilation, depending on the platform. -These are the highlights from the change-log since ncurses 5.1 release. +These are the highlights from the change-log since ncurses 5.5 release. <p> Interface changes: <ul> - <li>change type of <code>ospeed</code> variable back to - <code>short</code> to match its use in legacy applications. It was - altered after ncurses 4.2 to <code>speed_t</code> to repair a type - mismatch which was introduced after 1.9.4 in 1995. The principal - users of termcap continued to use <code>short</code>, which is - not the same size. - <p> - <em>NOTE</em>: A few applications will have to be recompiled - (about 1% of the programs in a typical Linux distribution, - 10% of the programs that use ncurses). These are easy to - identify with <code>nm</code> or <code>strings</code>. - - <li>remove a private function <code>_nc_can_clear_with()</code>, which - was built with the configure --enable-expanded option but not used. - - <li>add several private functions (prefixed with "_nc_") for tracing - <code>chtype</code> values in the debug library, and for better - access and buffer limit checking. + <li>generate linkable stubs for some macros: + <br> + getbegx, getbegy, getcurx, getcury, getmaxx, getmaxy, getparx, + getpary, getpary, + <br> + and (for libncursesw) + <br> + wgetbkgrnd + </ul> New features and improvements: <ul> - <li>rewrote <code>tgoto()</code> to make it better support existing - termcap applications which use hardcoded strings rather than obtain - all of their information from the termcap file. If the string does - not appear to be a terminfo string (i.e., does not refer to a "%p" - parameter, or terminfo-style padding), and termcap support is configured, <code>tgoto()</code> - will interpret it as termcap. Otherwise, as before, it will use - <code>tparm()</code>. - - <li>to ensure that the <code>tgoto()</code> changes work properly, - added checks to <code>tic</code> which report capabilities that do - not reference the expected number of parameters. - - <li>new configure script options: + <li>library <ul> - <li>option <code>--disable-root-environ</code> adds runtime checks - which tell ncurses to disregard $TERMINFO and similar environment - variables if the current user is root, or running setuid/setgid. - - <li>option <code>--disable-assumed-color</code> allows you to use the - pre-5.1 convention of default colors used for color-pair 0 to be - configured (see assume_default_colors()). + <li>support hashed databases for the terminal descriptions. + This uses the Berkeley database, has been tested for + several versions on different platforms. + + <li>add <code>use_legacy_coding()</code> function to support + lynx's font-switching feature. + + <li>add extension <code>nofilter()</code>, to cancel a prior + <code>filter()</code> call. + + <li>add/install a package config script, e.g., + <code>ncurses5-config</code> or + <code>ncursesw5-config</code>, according to + configuration options. + + <li>provide ifdef for <code>NCURSES_NOMACROS</code> which + suppresses most macro definitions from curses.h, i.e., + where a macro is defined to override a function to improve + performance. + + <li>make ifdef's consistent in <code>curses.h</code> for the + extended colors so the header file can be used for the + normal curses library. The header file installed for + extended colors is a variation of the wide-character + configuration. + + <li>improve <code>tgetstr()</code> by making the return value + point into the user's buffer, if provided. + + <li>add ifdef's allowing ncurses to be built with + <code>tparm()</code> using either varargs (the existing + status), or using a fixed-parameter list (to match X/Open). + + <li>widen the test for xterm <code>kmous</code> a little to + <code>allow</code> for other + strings than "\E[M", e.g., for <code>xterm-sco</code> + functionality in xterm. + + <li>modify <code>wgetnstr()</code> to return + <code>KEY_RESIZE</code> if a sigwinch occurs. + + <li>move prototypes for wide-character trace functions from + curses.tail to curses.wide to avoid accidental reference to + those if <code>_XOPEN_SOURCE_EXTENDED</code> is defined + without ensuring that <wchar.h> is included. + + <li>change the way shared libraries (other than libtool) are + installed. Rather than copying the build-tree's libraries, + link the shared objects into the install directory. This + makes the <code>--with-rpath</code> option work except with + <code>$(DESTDIR)</code>. + + <li>several improvements for rendering in hpterm. These are + only available if the library is configured using + <code>--enable-xmc-glitch</code>. + + <li>Add <code>NCURSES_NO_HARD_TABS</code> and + <code>NCURSES_NO_MAGIC_COOKIE</code> environment variables + to allow runtime suppression of the related hard-tabs and + xmc-glitch features. + </ul> - <li>implement configure script options that transform installed - program names, e.g., <code>--program-prefix</code>, including the - manpage names and cross references. + <li>programs: + <ul> + <li>add new test programs: chgat.c, demo_altkeys.c, + echochar.c, foldkeys.c, movewindow.c, redraw.c, (noting + that existing test programs also were modified to test + additional features). - <li>option <code>--with-database</code> allows you to specify a - different terminfo source-file to install. On OS/2 EMX, the - default is misc/emx.src, otherwise misc/terminfo.src + <li>modify tack to test extended capability function-key + strings. - <li>option <code>--with-default-terminfo-dir</code> allows you to - specify the default terminfo database directory. + <li>modify toe to access termcap data, e.g., via <code>cgetent()</code> + functions, or as a text file if those are not available. - <li>option <code>--with-libtool</code> allows you to build with - <code>libtool</code>. <p> <em>NOTE</em>: <code>libtool</code> - uses a different notation for numbering shared library versions - from the existing ncurses configuration. + <li>improve infocmp/tic <code>-f</code> option formatting. - <li>option <code>--with-manpage-tbl</code> causes the manpages to be - preprocessed by tbl(1) prior to installation, + <li>add <code>toe -a</code> option, to show all databases. + This uses new private interfaces in the ncurses library for + iterating through the list of databases. - <li>option <code>--without-curses-h</code> causes the installation - process to install curses.h as ncurses.h and make appropriate - changes to headers and manpages. + <li>modify <code>MKfallback.sh</code> to use + <code>tic -x</code> when constructing fallback tables to + allow extended capabilities to be retrieved from a fallback entry. </ul> - <li>modified configure script options: + <li>terminal database <ul> - <li>change symbol used by the <code>--install-prefix</code> configure - option from <code>INSTALL_PREFIX</code> to <code>DESTDIR</code> - (the latter has become common usage although the name is - misleading). - - <li>modify <code>ld -rpath</code> options (e.g., Linux, and Solaris) - to use an absolute pathname for the build tree's lib directory, - avoiding confusion with directories relative to the current one - with the installed programs. - - <li>modified <code>misc/run_tic.in</code> to use - <code>tic -o</code>, to eliminate dependency on - <code>$TERMINFO</code> variable for installs. + <li>add terminfo entries for xfce terminal (xfce) and multi gnome terminal (mgt) + <li>add nsterm-16color entry + <li>updated mlterm terminfo entry + <li>add kon, kon2 and jfbterm terminfo entry + <li>remove invis capability from klone+sgr, mainly used by linux entry, since it does not really do this + <li>add ka2, kb1, kb3, kc2 to vt220-keypad as an extension + <li>add shifted up/down arrow codes to xterm-new as kind/kri strings + <li>add hpterm-color terminfo entry + <li>add 256color variants of terminfo entries for programs which are reported to implement this feature + <li>correct order of use-clauses in rxvt-basic entry which made codes for f1-f4 vt100-style rather than vt220-style. </ul> +</ul> +Major bug fixes: +<ul> + <li>correct a typo in configure <code>--with-bool</code> option for the + case where <code>--without-cxx</code> is used. - <li>terminfo database: - <ul> - <li>updated xterm terminfo entries to match XFree86 xterm patch #146. + <li>move assignment from environment variable <code>ESCDELAY</code> + from <code>initscr()</code> down to <code>newterm()</code> so the + environment variable affects timeouts for terminals opened with + newterm() as well. - <li>added amiga-vnc, - Matrix Orbital, and - QNX qansi to misc/terminfo.src. + <li>modify <code>werase</code> to clear multicolumn characters that + extend into a derived window. - <li>added os2 entry to misc/emx.src. + <li>modify <code>wchgat()</code> to mark updated cells as changed so a + refresh will repaint those cells. - <li>add S0 and E0 extensions to <code>screen</code>'s terminfo entry - since otherwise the FreeBSD port makes it pass termcap equivalents - to <code>tgoto</code>, which would be misinterpreted by older - versions of ncurses. - </ul> + <li>correct logic in <code>wadd_wch()</code> and + <code>wecho_wch()</code>, which did not guard against passing the + multi-column attribute into a call on <code>waddch()</code>, e.g., + using data returned by <code>win_wch()</code> - <li>improvements to program usability: - <ul> - <li>modify programs to use <code>curses_version()</code> string to - report the version of ncurses with which they are compiled rather - than the NCURSES_VERSION string. The function returns the patch - level in addition to the major and minor version numbers. + <li>fix redrawing of windows other than <code>stdscr</code> using + <code>wredrawln()</code> by touching the corresponding rows in + <code>curscr</code>. - <li>modify <code>tput</code> program so it can be renamed or invoked via a link as - 'reset' or 'init', producing the same effect as <code>tput reset</code> or <code>tput init</code>. + <li>reduce memory leaks in repeated calls to <code>tgetent()</code> by + remembering the last <code>TERMINAL*</code> value allocated to hold + the corresponding data and freeing that if the + <code>tgetent()</code> result buffer is the same as the previous + call. - <li>add error checking to infocmp's -v and -m options to ensure that - the option value is indeed a number. - </ul> + <li>modify <code>read_termtype()</code> so the <code>term_names</code> + data is always allocated as part of the <code>str_table</code>, a + better fix for a memory leak. - <li>improved performance: - <ul> - <li>replace a lookup table in lib_vidattr.c used to decode - <code>no_color_video</code> with a logic expression which is faster. - </ul> + <li>fix <code>wins_nwstr(),</code> which did not handle single-column + non-8bit codes. + + <li>modify <code>wbkgrnd()</code> to avoid clearing the + <code>A_CHARTEXT</code> attribute bits since those record the state + of multicolumn characters. + + <li>improve <code>SIGWINCH</code> handling by postponing its effect + during <code>newterm()</code>, etc., when allocating screens. + + <li>remove 970913 feature for copying subwindows as they are moved in + <code>mvwin()</code>. + <li>add checks in <code>waddchnstr()</code> and + <code>wadd_wchnstr()</code> to stop copying when a null character + is found. + + <li>add some checks to ensure current position is within scrolling + region before scrolling on a new line. + + <li>add a workaround to ACS mapping to allow applications such as + test/blue.c to use the "PC ROM" characters by masking them with + A_ALTCHARSET. This worked up til 5.5, but was lost in the revision + of legacy coding. </ul> -Major bug fixes: + +Portability: <ul> - <li>correct <code>manlinks.sed</code> script introduced in ncurses 5.1 - to avoid using ERE "\+", which is not understood by standard versions - of <code>sed</code>. This happens to work with GNU <code>sed</code>, - but is not portable, and was the initial motivation for this release. - - <li>remove "hpux10.*" case from CF_SHARED_OPTS configure script macro. - This differed from the "hpux*" case by using reversed symbolic - links, which made the 5.1 version not match the configuration of - 5.0 shared libraries. - - <li>guard against corrupt terminfo data: - <ul> - <li>modify <code>tparm()</code> to disallow arithmetic on strings, - analyze the varargs list to read strings as strings and numbers as - numbers. - - <li>modify <code>tparm()</code>'s internal function - <code>spop()</code> to treat a null pointer as an empty string. - - <li>modify <code>parse_format()</code> in lib_tparm.c to ignore - precision if it is longer than 10000. - - <li>rewrote limit checks in lib_mvcur.c using new functions - <code>_nc_safe_strcat()</code>, etc. Made other related changes to - check lengths used for <code>strcat()</code> and - <code>strcpy()</code>. - </ul> - - <li>corrections to screen optimization: - <ul> - <li>added special case in lib_vidattr.c to reset underline and - standout for devices that have no sgr0 defined. - - <li>change handling of <code>non_dest_scroll_region</code> in - tty_update.c to clear text after it is shifted in rather than before - shifting out. Also correct row computation. - - <li>modify <code>rs2</code> capability in xterm-r6 and similar entries - where cursor save/restore bracketed the sequence for resetting video - attributes. The cursor restore would undo that. - </ul> - - <li>UTF-8 support: - <ul> - <li>when checking LC_ALL, LC_CTYPE, and LANG environment variables - for UTF-8 locale, ignore those which are set to an empty value, as - per SUSV2. + <li>configure script: + <ul> + <li>new options: + <dl> - <li>encode 0xFFFD in UTF-8 with 3 bytes, not 2. + <dt>--with-hashed-db + <dd>Use Berkeley hashed database for storing terminfo data rather than storing + each compiled entry in a separate binary file within a directory + tree. - <li>modify <code>_nc_utf8_outch()</code> to avoid sign-extension when - checking for out-of-range value. - </ul> + <dt>--without-dlsym + <dd>Do not use <code>dlsym()</code> to load GPM dynamically. - <li>other library fixes: - <ul> - <li>added checks for an empty <code>$HOME</code> environment - variable, to avoid retrieving terminfo descriptions from - <code>./.terminfo</code> . + <dt>--with-valgrind + <dd>Simplify building for testing with valgrind. - <li>change functions <code>_nc_parse_entry()</code> and - <code>postprocess_termcap()</code> to avoid using - <code>strtok()</code>, because it is non-reentrant. + <dt>--enable-wgetch-events + <dd>Compile with experimental wgetch-events code. - <li>initialize <code>fds[]</code> array to 0's in - <code>_nc_timed_wait()</code>; apparently <code>poll()</code> only - sets the <code>revents</code> members of that array when there is - activity corresponding to the related file. + <dt>--enable-signed-char + <dd>Store booleans in "signed char" rather than "char". - <li>add a check for null pointer in <code>Make_Enum_Type()</code>. + </dl> - <li>fix a heap problem with the c++ binding. + <li>improved options: + <dl> - <li>correct missing includes for <string.h> in several places, - including the C++ binding. This is not noted by gcc unless we use - the <code>-fno-builtin</code> option. - </ul> + <dt>--disable-largefile + <dd>make the option work both ways. - <li>several fixes for tic: - <ul> - <li>add a check for empty buffers returned by <code>fgets()</code> in - comp_scan.c <code>next_char()</code> function, in case - <code>tic</code> is run on a non-text file (fixes a core dump). - - <li>modify <code>tic</code> to verify that its inputs are really files, - in case someone tries to read a directory (or - <code>/dev/zero</code>). - - <li>correct an uninitialized parameter to <code>open_tempfile()</code> - in tic.c which made "tic -I" give an ambiguous error message about - <code>tmpnam</code>. - - <li>correct logic in <code>adjust_cancels()</code>, which did not check - both alternatives when reclassifying an extended name between - boolean, number and string, causing an infinite loop in - <code>tic</code>. - </ul> - - <li>using new checks in <code>tic</code> for parameter counts in - capability strings, found/fixed several errors both in the - terminfo database and in the include/Caps file. - <ul> - <li>modified several terminfo capability strings, including the - definitions for setaf, setab, in include/Caps to indicate that the - entries are parameterized. This information is used to tell which - strings are translated when converting to termcap. This fixes a - problem where the generated termcap would contain a spurious "%p1" - for the terminfo "%p1%d". - - <li>correct parameter counts in include/Caps for dclk as well as some - printer-specific capabilities: csnm, defc, scs, scsd, smgtp, smglp. - </ul> - - <li>various fixes for install scripts used to support configure - <code>--srcdir</code> and <code>--with-install-prefix</code>. - - <li>correct several mismatches between manpage filename and ".TH" - directives, renaming dft_fgbg.3x to default_colors.3x and - menu_attribs.3x to menu_attributes.3x. -</ul> + <dt>--with-gpm + <dd>The option now accepts a parameter, + i.e., the name of the dynamic GPM library to load via + <code>dlopen()</code> -Portability: -<ul> - <li>configure script: - <ul> - <li>newer config.guess, config.sub, including changes to support OS/2 - EMX. The configure script for OS/2 EMX still relies on a patch - since there is no (working) support for that platform in the main - autoconf distribution. + <dt>--disable-symlinks + <dd>The option now allows one to + disable <code>symlink()</code> in <code>tic</code> even when + <code>link()</code> does not work. + + </dl> + + </ul> + + <li>other configure/build issues: <ul> <li>remove special case for + Darwin in <code>CF_XOPEN_SOURCE</code> configure macro. - <li>make configure script checks on variables <code>$GCC</code> and - <code>$GXX</code> consistently compare against 'yes' rather than - test if they are nonnull, since either may be set to the - corresponding name of the C or C++ compiler. + <li>add configure check to ensure that <code>SIGWINCH</code> is + defined on platforms such as OS X which exclude that when + <code>_XOPEN_SOURCE,</code> etc., are defined - <li>change configure script to use AC_CANONICAL_SYSTEM rather than - AC_CANONICAL_HOST, which means that <code>configure --target</code> - will set a default program-prefix. + <li>use ld's <code>-search_paths_first</code> option on Darwin + to work around odd search rules on that platform. - <li>modify the check for big-core to force a couple of memory - accesses, which may work as needed for older/less-capable machines - (if not, there's still the explicit configure option). + <li>improve ifdef's for <code>_POSIX_VDISABLE</code> in tset to + work with Mac OS X. - <li>modify configure test for <code>tcgetattr()</code> to allow for - old implementations, e.g., on BeOS, which only defined it as a - macro. + <li>modify configure script to ensure that if the C compiler is + used rather than the loader in making shared libraries, the + <code>$(CFLAGS)</code> variable is also used. - <li>add configure check for filesystems (such as OS/2 EMX) which do - not distinguish between upper/lowercase filenames, use this to fix - tags rules in makefiles. + <li>use <code>${CC}</code> rather than <code>${LD}</code> in + shared library rules for IRIX64, Solaris to help ensure + that initialization sections are provided for extra linkage + requirements, e.g., of C++ applications. - <li>add MKncurses_def.sh to generate fallback definitions for - ncurses_cfg.h, to quiet gcc -Wundef warnings, modified ifdef's in - code to consistently use "#if" rather than "#ifdef". + <li>improve some shared-library configure scripting for Linux, + FreeBSD and NetBSD to make + <code>--with-shlib-version</code> work. - <li>change most remaining unquoted parameters of <code>test</code> in - configure script to use quotes, for instance fixing a problem in the - <code>--disable-database</code> option. + <li>split up dependency of <code>names.c</code> and + <code>codes.c</code> in <code>ncurses/Makefile</code> to + work with parallel make. - <li>modify scripts so that "make install.data" works on OS/2 EMX. + <li>modify <code>MKlib_gen.sh</code> to change + preprocessor-expanded <code>_Bool</code> back to <code>bool</code>. - <li>modify scripts and makefiles so the Ada95 directory builds on - OS/2 EMX. + <li>modify <code>progs/Makefile.in</code> to make + <code>tput init</code> work properly with cygwin, + i.e., do not pass a <code>.exe</code> in the reference + string used in check_aliases. </ul> <li>library: <ul> - <li>replaced case-statement in <code>_nc_tracebits()</code> for CSIZE - with a table to simplify working around implementations that define - random combinations of the related macros to zero. + <li>ignore wide-acs line-drawing characters that + <code>wcwidth()</code> claims are not one-column. This is + a workaround for Solaris' broken locale support. - <li>improved OS/2 mouse support by retrying as a 2-button mouse if code - fails to set up a 3-button mouse. + <li>reduce name-pollution in <code>term.h</code> by removing + <code>#define</code>'s for HAVE_xxx symbols. - <li>added private entrypoint <code>_nc_basename()</code>, used to - consolidate related code in progs, as well as accommodating OS/2 EMX - pathnames. + <li>fix <code>#ifdef</code> in <code>c++/internal.h</code> for + QNX 6.1 + </ul> - <li>alter definition of NCURSES_CONST to make it non-empty. + <li>test programs: <ul> <li>modify <code>test/configure</code> script + to allow building test programs with PDCurses/X11. - <li>redefine 'TEXT' in menu.h for AMIGA, since it is reported to have - an (unspecified) symbol conflict. - </ul> + <li>modified test programs to allow some to work with NetBSD + curses. Several do not because NetBSD curses implements a + subset of X/Open curses, and also lacks much of SVr4 + additions. But it is enough for comparison. - <li>programs: - <ul> - <li>modified progs/tset.c and tack/sysdep.c to build with sgttyb - interface if neither termio or termios is available. Tested this - with FreeBSD 2.1.5 (which does have termios - but the sgttyb does - work). - </ul> + <li>improved <code>test/configure</code> to build test/ncurses + on HPUX 11 using the vendor curses. + <li>change configure script to produce + <code>test/Makefile</code> from data file. + </ul> </ul> <H1>Features of Ncurses</H1> @@ -387,14 +390,15 @@ The ncurses package also has many useful extensions over SVr4: <UL> <LI>The API is 8-bit clean and base-level conformant with the X/OPEN curses specification, XSI curses (that is, it implements all BASE level features, -but not all EXTENDED features). Most EXTENDED-level features not directly -concerned with wide-character support are implemented, including many -function calls not supported under SVr4 curses (but portability of all +and most EXTENDED features). +It includes many function calls not supported under SVr4 curses +(but portability of all calls is documented so you can use the SVr4 subset only). <LI>Unlike SVr3 curses, ncurses can write to the rightmost-bottommost corner of the screen if your terminal has an insert-character capability. <LI>Ada95 and C++ bindings. -<LI>Support for mouse event reporting with X Window xterm and OS/2 console windows. +<LI>Support for mouse event reporting with X Window xterm +and FreeBSD and OS/2 console windows. <LI>Extended mouse support via Alessandro Rubini's gpm package. <LI>The function <CODE>wresize()</CODE> allows you to resize windows, preserving their data. @@ -406,7 +410,7 @@ and <CODE>define_key()</CODE> allow you to better control the use of function keys, e.g., disabling the ncurses KEY_MOUSE, or by defining more than one control sequence to map to a given key code. -<LI>Support for 16-color terminals, such as aixterm and XFree86 xterm. +<LI>Support for 16-color terminals, such as aixterm and modern xterm. <LI>Better cursor-movement optimization. The package now features a cursor-local-movement computation more efficient than either BSD's or System V's. @@ -474,61 +478,61 @@ including (versions starting with those noted): <DT> cdk <DD> Curses Development Kit <br> -<A HREF="http://www.vexus.ca/CDK.html">http://www.vexus.ca/CDK.html</a> +<A HREF="http://invisible-island.net/cdk/">http://invisible-island.net/cdk/</A> <br> -<A HREF="http://dickey.his.com/cdk/cdk.html">http://dickey.his.com/cdk</A>. +<A HREF="http://www.vexus.ca/products/CDK/">http://www.vexus.ca/products/CDK/</a> <DT> ded <DD> directory-editor <br> -<A HREF="http://dickey.his.com/ded/ded.html">http://dickey.his.com/ded</A>. +<A HREF="http://invisible-island.net/ded/">http://invisible-island.net/ded/</A> <DT> dialog <DD> the underlying application used in Slackware's setup, and the basis for similar applications on GNU/Linux. <br> -<A HREF="http://dickey.his.com/dialog/dialog.html">http://dickey.his.com/dialog</A>. +<A HREF="http://invisible-island.net/dialog/">http://invisible-island.net/dialog/</A> <DT> lynx <DD> the character-screen WWW browser <br> -<A HREF="http://lynx.isc.org/release/">http://lynx.isc.org/release</A>. -<DT> Midnight Commander 4.1 +<A HREF="http://lynx.isc.org/release/">http://lynx.isc.org/release/</A> +<DT> Midnight Commander <DD> file manager <br> -<A HREF="www.gnome.org/mc/">www.gnome.org/mc/</A>. +<A HREF="http://www.ibiblio.org/mc/">http://www.ibiblio.org/mc/</A> <DT> mutt <DD> mail utility <br> -<A HREF="http://www.mutt.org">http://www.mutt.org</A>. +<A HREF="http://www.mutt.org/">http://www.mutt.org/</A> <DT> ncftp <DD> file-transfer utility <br> -<A HREF="http://www.ncftp.com">http://www.ncftp.com</A>. +<A HREF="http://www.ncftp.com/">http://www.ncftp.com/</A> <DT> nvi <DD> New vi versions 1.50 are able to use ncurses versions 1.9.7 and later. <br> -<A HREF="http://www.bostic.com/vi/">http://www.bostic.com/vi/</A>. +<A HREF="http://www.bostic.com/vi/">http://www.bostic.com/vi/</A> +<br> +<DT> pinfo +<DD> Lynx-like info browser. +<A HREF="http://dione.ids.pl/~pborys/software/pinfo/">http://dione.ids.pl/~pborys/software/pinfo/</A> <DT> tin <DD> newsreader, supporting color, MIME -<br> -<A HREF="http://www.tin.org">http://www.tin.org</A>. -<DT> taper -<DD> tape archive utility -<br> -<A HREF="http://members.iinet.net.au/~yusuf/taper/">http://members.iinet.net.au/~yusuf/taper/</A>. +<A HREF="http://www.tin.org/">http://www.tin.org/</A> <DT> vh-1.6 <DD> Volks-Hypertext browser for the Jargon File <br> -<A HREF="http://www.bg.debian.org/Packages/unstable/text/vh.html">http://www.bg.debian.org/Packages/unstable/text/vh.html</A>. +<A HREF="http://www.debian.org/Packages/unstable/text/vh.html">http://www.debian.org/Packages/unstable/text/vh.html</A> </DL> as well as some that use ncurses for the terminfo support alone: <DL> <DT> minicom <DD> terminal emulator <br> -<A HREF="http://www.pp.clinet.fi/~walker/minicom.html">http://www.pp.clinet.fi/~walker/minicom.html</A>. +<A HREF="http://alioth.debian.org/projects/minicom/"> +http://alioth.debian.org/projects/minicom/</A> <DT> vile <DD> vi-like-emacs <br> -<A HREF="http://dickey.his.com/vile/vile.html">http://dickey.his.com/vile</A>. +<A HREF="http://invisible-island.net/vile/">http://invisible-island.net/vile/</A> </DL> <P> @@ -537,16 +541,16 @@ a few games). <H2>Who's Who and What's What</H2> -The original developers of ncurses are <A -HREF="mailto:zmbenhal@netcom.com">Zeyd Ben-Halim</A> and -<A HREF="http://www.ccil.org/~esr/home.html">Eric S. Raymond</A>. +Zeyd Ben-Halim +started it from a previous package pcurses, written by Pavel Curtis. +Eric S. Raymond +continued development. +Jürgen Pfeifer wrote most of the form and menu libraries. Ongoing work is being done by -<A HREF="mailto:dickey@herndon4.his.com">Thomas Dickey</A> -and -<A HREF="mailto:juergen.pfeifer@gmx.net">Jürgen Pfeifer</A>. -<A HREF="mailto:dickey@herndon4.his.com">Thomas Dickey</A> -acts as the maintainer for the Free Software Foundation, which holds the -copyright on ncurses. +<A HREF="mailto:dickey@invisible-island.net">Thomas Dickey</A>. +Thomas Dickey +acts as the maintainer for the Free Software Foundation, +which holds the copyright on ncurses. Contact the current maintainers at <A HREF="mailto:bug-ncurses@gnu.org">bug-ncurses@gnu.org</A>. <P> @@ -561,7 +565,7 @@ This list is open to anyone interested in helping with the development and testing of this package.<P> Beta versions of ncurses and patches to the current release are made available at -<A HREF="ftp://dickey.his.com/ncurses">ftp://dickey.his.com/ncurses</A>. +<A HREF="ftp://invisible-island.net/ncurses/">ftp://invisible-island.net/ncurses/</A> . <H2>Future Plans</H2> <UL> @@ -573,14 +577,17 @@ on them, please join the ncurses list. <H2>Other Related Resources</H2> -The distribution includes and uses a version of the terminfo-format -terminal description file maintained by Eric Raymond. -<A HREF="http://earthspace.net/~esr/terminfo">http://earthspace.net/~esr/terminfo</A>.<P> +The distribution provides a newer version of the terminfo-format +terminal description file once maintained by +<A HREF="http://www.catb.org/~esr/terminfo/">Eric Raymond</A> . +Unlike the older version, the termcap and terminfo data are provided +in the same file, and provides several user-definable extensions +beyond the X/Open specification.<P> You can find lots of information on terminal-related topics not covered in the terminfo file at <A HREF="http://www.cs.utk.edu/~shuford/terminal_index.html">Richard Shuford's -archive</A>. +archive</A> . </BODY> </HTML> <!-- diff --git a/contrib/ncurses/doc/html/hackguide.html b/contrib/ncurses/doc/html/hackguide.html index ce033a1..97d1369 100644 --- a/contrib/ncurses/doc/html/hackguide.html +++ b/contrib/ncurses/doc/html/hackguide.html @@ -1,11 +1,39 @@ <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 3.0//EN"> <!-- - $Id: hackguide.html,v 1.25 2000/03/25 18:45:21 tom Exp $ + $Id: hackguide.html,v 1.27 2005/12/24 15:37:13 tom Exp $ + **************************************************************************** + * Copyright (c) 1998-2003,2005 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. * + **************************************************************************** --> <HTML> <HEAD> <TITLE>A Hacker's Guide to Ncurses Internals</TITLE> <link rev="made" href="mailto:bugs-ncurses@gnu.org"> +<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> <!-- This document is self-contained, *except* that there is one relative link to the ncurses-intro.html document, expected to be in the same directory with @@ -286,10 +314,6 @@ header comments of <CODE>hardscroll.c</CODE> and <CODE>hashmap.c</CODE>; then tr it out. You can also test the hardware-scrolling optimization separately with <CODE>hardscroll</CODE>. <P> -There's one other interactive tester, <CODE>tctest</CODE>, that exercises -translation between termcap and terminfo formats. If you have a serious -need to run this, you probably belong on our development team! - <H1><A NAME="ncurslib">A Tour of the Ncurses Library</A></H1> <H2><A NAME="loverview">Library Overview</A></H2> @@ -377,7 +401,7 @@ trace_buf.c </code> </blockquote> It is rather unlikely you will ever need to change these, unless -you want to introduce a new debug trace level for some reasoon.<P> +you want to introduce a new debug trace level for some reason.<P> There is another group of files that do direct I/O via <EM>tputs()</EM>, computations on the terminal capabilities, or queries to the OS @@ -558,7 +582,7 @@ Then <CODE>lib_doupdate.c</CODE> goes to work. Its job is to do line-by-line transformations of <CODE>curscr</CODE> lines to <CODE>newscr</CODE> lines. Its main tool is the routine <CODE>mvcur()</CODE> in <CODE>lib_mvcur.c</CODE>. This routine does cursor-movement optimization, attempting to get from given screen -location A to given location B in the fewest output characters posible. <P> +location A to given location B in the fewest output characters possible. <P> If you want to work on screen optimizations, you should use the fact that (in the trace-enabled version of the library) enabling the diff --git a/contrib/ncurses/doc/html/ncurses-intro.html b/contrib/ncurses/doc/html/ncurses-intro.html index bdc5fa0..e62ead7 100644 --- a/contrib/ncurses/doc/html/ncurses-intro.html +++ b/contrib/ncurses/doc/html/ncurses-intro.html @@ -1,11 +1,39 @@ <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 3.0//EN"> <!-- - $Id: ncurses-intro.html,v 1.35 2001/09/02 00:23:11 tom Exp $ + $Id: ncurses-intro.html,v 1.41 2005/12/24 15:47:05 tom Exp $ + **************************************************************************** + * Copyright (c) 1998-2004,2005 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. * + **************************************************************************** --> <HTML> <HEAD> <TITLE>Writing Programs with NCURSES</TITLE> <link rev="made" href="mailto:bugs-ncurses@gnu.org"> +<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> </HEAD> <BODY> @@ -221,16 +249,11 @@ maintainer of this package is <esr@snark.thyrsus.com> wrote many of the new features in versions after 1.8.1 and wrote most of this introduction. -<A HREF="mailto:juergen.pfeifer@gmx.net">Jürgen Pfeifer</A> +Jürgen Pfeifer wrote all of the menu and forms code as well as the <A HREF="http://www.adahome.com">Ada95</A> binding. Ongoing work is being done by -<A HREF="mailto:dickey@herndon4.his.com">Thomas Dickey</A> -and -<A HREF="mailto:juergen.pfeifer@gmx.net">Jürgen Pfeifer</A>. -<A HREF="mailto:florian@gnu.org">Florian La Roche</A> -acts as the maintainer for the Free Software Foundation, which holds the -copyright on ncurses. +<A HREF="mailto:dickey@invisible-island.net">Thomas Dickey</A> (maintainer). Contact the current maintainers at <A HREF="mailto:bug-ncurses@gnu.org">bug-ncurses@gnu.org</A>. <P> @@ -613,6 +636,7 @@ Presently, mouse event reporting works in the following environments: <li>xterm and similar programs such as rxvt. <li>Linux console, when configured with <CODE>gpm</CODE>(1), Alessandro Rubini's mouse server. +<li>FreeBSD sysmouse (console) <li>OS/2 EMX </ul> <P> @@ -690,7 +714,7 @@ the first call to <CODE>refresh()</CODE> will clear the screen. If an error occurs a message is written to standard error and the program exits. Otherwise it returns a pointer to stdscr. A few functions may be called before initscr (<CODE>slk_init()</CODE>, <CODE>filter()</CODE>, -<CODE>ripofflines()</CODE>, <CODE>use_env()</CODE>, and, if you are using multiple +<CODE>ripoffline()</CODE>, <CODE>use_env()</CODE>, and, if you are using multiple terminals, <CODE>newterm()</CODE>.) <DT> <CODE>endwin()</CODE> <DD> Your program should always call <CODE>endwin()</CODE> before exiting or @@ -732,7 +756,7 @@ the terminal, as other routines merely manipulate data structures. <CODE>wrefresh()</CODE> copies the named window to the physical terminal screen, taking into account what is already there in order to do optimizations. <CODE>refresh()</CODE> does a -refresh of <CODE>stdscr()</CODE>. Unless <CODE>leaveok()</CODE> has been +refresh of <CODE>stdscr</CODE>. Unless <CODE>leaveok()</CODE> has been enabled, the physical cursor of the terminal is left at the location of the window's cursor. <DT> <CODE>doupdate()</CODE> and <CODE>wnoutrefresh(win)</CODE> @@ -982,7 +1006,7 @@ on and refresh them, the changes made to the overlapping region under historic To understand why this is a problem, remember that screen updates are calculated between two representations of the <EM>entire</EM> display. The -documentation says that when you refresh a window, it is first copied to to the +documentation says that when you refresh a window, it is first copied to the virtual screen, and then changes are calculated to update the physical screen (and applied to the terminal). But "copied to" is not very specific, and subtle differences in how copying works can produce different behaviors in the @@ -1020,7 +1044,7 @@ guarantee an entire-contents copy anywhere. <P> The really clean way to handle this is to use the panels library. If, when you want a screen update, you do <CODE>update_panels()</CODE>, it will -do all the necessary <CODE>wnoutrfresh()</CODE> calls for whatever panel +do all the necessary <CODE>wnoutrefresh()</CODE> calls for whatever panel stacking order you have defined. Then you can do one <CODE>doupdate()</CODE> and there will be a <EM>single</EM> burst of physical I/O that will do all your updates. @@ -1222,10 +1246,10 @@ The general flow of control of a menu program looks like this: <LI>Initialize <CODE>curses</CODE>. <LI>Create the menu items, using <CODE>new_item()</CODE>. <LI>Create the menu using <CODE>new_menu()</CODE>. -<LI>Post the menu using <CODE>menu_post()</CODE>. +<LI>Post the menu using <CODE>post_menu()</CODE>. <LI>Refresh the screen. <LI>Process user requests via an input loop. -<LI>Unpost the menu using <CODE>menu_unpost()</CODE>. +<LI>Unpost the menu using <CODE>unpost_menu()</CODE>. <LI>Free the menu, using <CODE>free_menu()</CODE>. <LI>Free the items using <CODE>free_item()</CODE>. <LI>Terminate <CODE>curses</CODE>. @@ -1308,8 +1332,8 @@ refreshed or erased at post/unpost time. The inner window or By default, both windows are <CODE>stdscr</CODE>. You can set them with the functions in <CODE>menu_win(3x)</CODE>. <P> -When you call <CODE>menu_post()</CODE>, you write the menu to its -subwindow. When you call <CODE>menu_unpost()</CODE>, you erase the +When you call <CODE>post_menu()</CODE>, you write the menu to its +subwindow. When you call <CODE>unpost_menu()</CODE>, you erase the subwindow, However, neither of these actually modifies the screen. To do that, call <CODE>wrefresh()</CODE> or some equivalent. @@ -1441,10 +1465,10 @@ The general flow of control of a form program looks like this: <LI>Initialize <CODE>curses</CODE>. <LI>Create the form fields, using <CODE>new_field()</CODE>. <LI>Create the form using <CODE>new_form()</CODE>. -<LI>Post the form using <CODE>form_post()</CODE>. +<LI>Post the form using <CODE>post_form()</CODE>. <LI>Refresh the screen. <LI>Process user requests via an input loop. -<LI>Unpost the form using <CODE>form_unpost()</CODE>. +<LI>Unpost the form using <CODE>unpost_form()</CODE>. <LI>Free the form, using <CODE>free_form()</CODE>. <LI>Free the fields using <CODE>free_field()</CODE>. <LI>Terminate <CODE>curses</CODE>. @@ -1480,7 +1504,7 @@ the screen (the third and fourth arguments, which must be zero or greater). Note that these coordinates are relative to the form subwindow, which will coincide with <CODE>stdscr</CODE> by default but need not be <CODE>stdscr</CODE> if you've done an explicit -<CODE>set_form_window()</CODE> call. <P> +<CODE>set_form_win()</CODE> call. <P> The fifth argument allows you to specify a number of off-screen rows. If this is zero, the entire field will always be displayed. If it is @@ -2519,13 +2543,13 @@ By default, all options are on. Here are the available option bits: <DL> <DT> O_NL_OVERLOAD <DD> Enable overloading of <CODE>REQ_NEW_LINE</CODE> as described in <A -NAME="fedit">Editing Requests</A>. The value of this option is +href="#fedit">Editing Requests</A>. The value of this option is ignored on dynamic fields that have not reached their size limit; these have no last line, so the circumstances for triggering a <CODE>REQ_NEXT_FIELD</CODE> never arise. <DT> O_BS_OVERLOAD <DD> Enable overloading of <CODE>REQ_DEL_PREV</CODE> as described in -<A NAME="fedit">Editing Requests</A>. +<A href="#fedit">Editing Requests</A>. </DL> The option values are bit-masks and can be composed with logical-or in |