<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE appendix PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
	  "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
<appendix id="compatibility_functions">
<title>Compatibility Functions</title>
<para>
The X Version 11 and X Version 10 functions discussed in this appendix 
are obsolete, have been superseded by newer X Version 11 functions,
and are maintained for compatibility reasons only.
</para>
<sect1 id="X_Version_11_Compatibility_Functions">
<title>X Version 11 Compatibility Functions</title>
<para>
You can use the X Version 11 compatibility functions to:
<itemizedlist>
  <listitem>
    <para>
Set standard properties 
    </para>
  </listitem>
  <listitem>
    <para>
Set and get window sizing hints 
    </para>
  </listitem>
  <listitem>
    <para>
Set and get an
<structname>XStandardColormap</structname>
structure 
    </para>
  </listitem>
  <listitem>
    <para>
Parse window geometry
    </para>
  </listitem>
  <listitem>
    <para>
Get X environment defaults
    </para>
  </listitem>
</itemizedlist>
</para>
<sect2 id="Setting_Standard_Properties">
<title>Setting Standard Properties</title>
<para>
To specify a minimum set of properties describing the simplest application,
use
<xref linkend='XSetStandardProperties' xrefstyle='select: title'/>.
This function has been superseded by
<xref linkend='XSetWMProperties' xrefstyle='select: title'/>
and sets all or portions of the 
<property>WM_NAME</property>, <property>WM_ICON_NAME</property>, <property>WM_HINTS</property>, <property>WM_COMMAND</property>, 
and <property>WM_NORMAL_HINTS</property> properties.
</para>
<indexterm significance="preferred"><primary>XSetStandardProperties</primary></indexterm>
<!-- .sM -->
<funcsynopsis id='XSetStandardProperties'>
<funcprototype>
  <funcdef><function>XSetStandardProperties</function></funcdef>
  <paramdef>Display<parameter> *display</parameter></paramdef>
  <paramdef>Window<parameter> w</parameter></paramdef>
  <paramdef>char<parameter> *window_name</parameter></paramdef>
  <paramdef>char<parameter> *icon_name</parameter></paramdef>
  <paramdef>Pixmap<parameter> icon_pixmap</parameter></paramdef>
  <paramdef>char<parameter> **argv</parameter></paramdef>
  <paramdef>int<parameter> argc</parameter></paramdef>
  <paramdef>XSizeHints<parameter> *hints</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<!-- .FN -->
<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies the connection to the X server.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the window.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>window_name</emphasis>
    </term>
    <listitem>
      <para>
Specifies the window name,
which should be a null-terminated string.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>icon_name</emphasis>
    </term>
    <listitem>
      <para>
Specifies the icon name,
which should be a null-terminated string.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>icon_pixmap</emphasis>
    </term>
    <listitem>
      <para>
Specifies the bitmap that is to be used for the icon or
<symbol>None</symbol>.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>argv</emphasis>
    </term>
    <listitem>
      <para>
Specifies the application's argument list.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>argc</emphasis>
    </term>
    <listitem>
      <para>
Specifies the number of arguments.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>hints</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer to the size hints for the window in its normal state.
    </para>
  </listitem>
  </varlistentry>
</variablelist>
<para>
<!-- .LP -->
<!-- .eM -->
The
<xref linkend='XSetStandardProperties' xrefstyle='select: title'/>
function provides a means by which simple applications set the
most essential properties with a single call.
<xref linkend='XSetStandardProperties' xrefstyle='select: title'/>
should be used to give a window manager some information about 
your program's preferences. 
It should not be used by applications that need
to communicate more information than is possible with
<xref linkend='XSetStandardProperties' xrefstyle='select: title'/>.
(Typically, argv is the argv array of your main program.)
If the strings are not in the Host Portable Character Encoding,
the result is implementation-dependent.
</para>
<para>
<!-- .LP -->
<xref linkend='XSetStandardProperties' xrefstyle='select: title'/>
can generate
<errorname>BadAlloc</errorname>
and
<errorname>BadWindow</errorname>
errors.
</para>
</sect2>
<sect2 id="Setting_and_Getting_Window_Sizing_Hints">
<title>Setting and Getting Window Sizing Hints</title>
<para>
Xlib provides functions that you can use to set or get window sizing hints.
The functions discussed in this section use the flags and the
<structname>XSizeHints</structname>
structure, as defined in the
<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>
<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
header file and use the <property>WM_NORMAL_HINTS</property> property.
</para>
<para>
<!-- .LP -->
<!-- .sp -->
To set the size hints for a given window in its normal state, use
<xref linkend='XSetNormalHints' xrefstyle='select: title'/>.
This function has been superseded by
<xref linkend='XSetWMNormalHints' xrefstyle='select: title'/>.
</para>
<indexterm significance="preferred"><primary>XSetNormalHints</primary></indexterm>
<!-- .sM -->
<funcsynopsis id='XSetNormalHints'>
<funcprototype>
  <funcdef><function>XSetNormalHints</function></funcdef>
  <paramdef>Display<parameter> *display</parameter></paramdef>
  <paramdef>Window<parameter> w</parameter></paramdef>
  <paramdef>XSizeHints<parameter> *hints</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<!-- .FN -->
<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies the connection to the X server.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the window.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>hints</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer to the size hints for the window in its normal state.
    </para>
  </listitem>
  </varlistentry>
</variablelist>
<para>
<!-- .LP -->
<!-- .eM -->
The
<xref linkend='XSetNormalHints' xrefstyle='select: title'/>
function sets the size hints structure for the specified window.
Applications use
<xref linkend='XSetNormalHints' xrefstyle='select: title'/>
to inform the window manager of the size
or position desirable for that window.
In addition, 
an application that wants to move or resize itself should call
<xref linkend='XSetNormalHints' xrefstyle='select: title'/>
and specify its new desired location and size
as well as making direct Xlib calls to move or resize.  
This is because window managers may ignore redirected
configure requests, but they pay attention to property changes.
</para>
<para>
<!-- .LP -->
To set size hints, 
an application not only must assign values to the appropriate members
in the hints structure but also must set the flags member of the structure 
to indicate which information is present and where it came from.  
A call to
<xref linkend='XSetNormalHints' xrefstyle='select: title'/>
is meaningless, unless the flags member is set to indicate which members of
the structure have been assigned values.
</para>
<para>
<!-- .LP -->
<xref linkend='XSetNormalHints' xrefstyle='select: title'/>
can generate
<errorname>BadAlloc</errorname>
and
<errorname>BadWindow</errorname>
errors.
</para>
<para>
<!-- .LP -->
<!-- .sp -->
To return the size hints for a window in its normal state, use
<xref linkend='XGetNormalHints' xrefstyle='select: title'/>.
This function has been superseded by
<xref linkend='XGetWMNormalHints' xrefstyle='select: title'/>.
</para>
<indexterm significance="preferred"><primary>XGetNormalHints</primary></indexterm>
<!-- .sM -->
<funcsynopsis id='XGetNormalHints'>
<funcprototype>
  <funcdef>Status <function>XGetNormalHints</function></funcdef>
  <paramdef>Display<parameter> *display</parameter></paramdef>
  <paramdef>Window<parameter> w</parameter></paramdef>
  <paramdef>XSizeHints<parameter> *hints_return</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<!-- .FN -->
<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies the connection to the X server.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the window.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>hints_return</emphasis>
    </term>
    <listitem>
      <para>
Returns the size hints for the window in its normal state.
    </para>
  </listitem>
  </varlistentry>
</variablelist>
<para>
<!-- .LP -->
<!-- .eM -->
The
<xref linkend='XGetNormalHints' xrefstyle='select: title'/>
function returns the size hints for a window in its normal state.
It returns a nonzero status if it succeeds or zero if
the application specified no normal size hints for this window.
</para>
<para>
<!-- .LP -->
<xref linkend='XGetNormalHints' xrefstyle='select: title'/>
can generate a
<errorname>BadWindow</errorname>
error.
</para>
<para>
<!-- .LP -->
<!-- .sp -->
The next two functions set and read the <property>WM_ZOOM_HINTS</property> property.
</para>
<para>
<!-- .LP -->
To set the zoom hints for a window, use
<xref linkend='XSetZoomHints' xrefstyle='select: title'/>.
This function is no longer supported by the
<citetitle>Inter-Client Communication Conventions Manual</citetitle>.
</para>
<indexterm significance="preferred"><primary>XSetZoomHints</primary></indexterm>
<!-- .sM -->
<funcsynopsis id='XSetZoomHints'>
<funcprototype>
  <funcdef><function>XSetZoomHints</function></funcdef>
  <paramdef>Display<parameter> *display</parameter></paramdef>
  <paramdef>Window<parameter> w</parameter></paramdef>
  <paramdef>XSizeHints<parameter> *zhints</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<!-- .FN -->
<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies the connection to the X server.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the window.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>zhints</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer to the zoom hints.
    </para>
  </listitem>
  </varlistentry>
</variablelist>
<para>
<!-- .LP -->
<!-- .eM -->
Many window managers think of windows in one of three states:
iconic, normal, or zoomed.
The
<xref linkend='XSetZoomHints' xrefstyle='select: title'/>
function provides the window manager with information for the window in the
zoomed state.
</para>
<para>
<!-- .LP -->
<xref linkend='XSetZoomHints' xrefstyle='select: title'/>
can generate
<errorname>BadAlloc</errorname>
and
<errorname>BadWindow</errorname>
errors.
</para>
<para>
<!-- .LP -->
<!-- .sp -->
To read the zoom hints for a window, use
<xref linkend='XGetZoomHints' xrefstyle='select: title'/>.
This function is no longer supported by the
<citetitle>Inter-Client Communication Conventions Manual</citetitle>.
</para>
<indexterm significance="preferred"><primary>XGetZoomHints</primary></indexterm>
<!-- .sM -->
<funcsynopsis id='XGetZoomHints'>
<funcprototype>
  <funcdef>Status <function>XGetZoomHints</function></funcdef>
  <paramdef>Display<parameter> *display</parameter></paramdef>
  <paramdef>Window<parameter> w</parameter></paramdef>
  <paramdef>XSizeHints<parameter> *zhints_return</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<!-- .FN -->
<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies the connection to the X server.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the window.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>zhints_return</emphasis>
    </term>
    <listitem>
      <para>
Returns the zoom hints.
    </para>
  </listitem>
  </varlistentry>
</variablelist>
<para>
<!-- .LP -->
<!-- .eM -->
The
<xref linkend='XGetZoomHints' xrefstyle='select: title'/>
function returns the size hints for a window in its zoomed state.
It returns a nonzero status if it succeeds or zero if
the application specified no zoom size hints for this window.
</para>
<para>
<!-- .LP -->
<xref linkend='XGetZoomHints' xrefstyle='select: title'/>
can generate a
<errorname>BadWindow</errorname>
error.
</para>
<para>
<!-- .LP -->
<!-- .sp -->
To set the value of any property of type <property>WM_SIZE_HINTS</property>, use
<xref linkend='XSetSizeHints' xrefstyle='select: title'/>.
This function has been superseded by
<xref linkend='XSetWMSizeHints' xrefstyle='select: title'/>.
</para>
<indexterm significance="preferred"><primary>XSetSizeHints</primary></indexterm>
<!-- .sM -->
<funcsynopsis id='XSetSizeHints'>
<funcprototype>
  <funcdef><function>XSetSizeHints</function></funcdef>
  <paramdef>Display<parameter> *display</parameter></paramdef>
  <paramdef>Window<parameter> w</parameter></paramdef>
  <paramdef>XSizeHints<parameter> *hints</parameter></paramdef>
  <paramdef>Atom<parameter> property</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<!-- .FN -->
<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies the connection to the X server.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the window.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>hints</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer to the size hints.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>property</emphasis>
    </term>
    <listitem>
      <para>
Specifies the property name.
    </para>
  </listitem>
  </varlistentry>
</variablelist>
<para>
<!-- .LP -->
<!-- .eM -->
The
<xref linkend='XSetSizeHints' xrefstyle='select: title'/>
function sets the
<structname>XSizeHints</structname>
structure for the named property and the specified window.
This is used by
<xref linkend='XSetNormalHints' xrefstyle='select: title'/>
and
<xref linkend='XSetZoomHints' xrefstyle='select: title'/>
and can be used to set the value of any property of type <property>WM_SIZE_HINTS</property>.
Thus, it may be useful if other properties of that type get defined.
</para>
<para>
<!-- .LP -->
<xref linkend='XSetSizeHints' xrefstyle='select: title'/>
can generate
<errorname>BadAlloc</errorname>,
<errorname>BadAtom</errorname>,
and
<errorname>BadWindow</errorname>
errors.
</para>
<para>
<!-- .LP -->
<!-- .sp -->
To read the value of any property of type <property>WM_SIZE_HINTS</property>, use
<xref linkend='XGetSizeHints' xrefstyle='select: title'/>.
This function has been superseded by
<xref linkend='XGetWMSizeHints' xrefstyle='select: title'/>.
</para>
<indexterm significance="preferred"><primary>XGetSizeHints</primary></indexterm>
<!-- .sM -->
<funcsynopsis id='XGetSizeHints'>
<funcprototype>
  <funcdef>Status <function>XGetSizeHints</function></funcdef>
  <paramdef>Display<parameter> *display</parameter></paramdef>
  <paramdef>Window<parameter> w</parameter></paramdef>
  <paramdef>XSizeHints<parameter> *hints_return</parameter></paramdef>
  <paramdef>Atom<parameter> property</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<!-- .FN -->
<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies the connection to the X server.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the window.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>hints_return</emphasis>
    </term>
    <listitem>
      <para>
Returns the size hints.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>property</emphasis>
    </term>
    <listitem>
      <para>
Specifies the property name.
    </para>
  </listitem>
  </varlistentry>
</variablelist>
<para>
<!-- .LP -->
<!-- .eM -->
The
<xref linkend='XGetSizeHints' xrefstyle='select: title'/>
function returns the
<structname>XSizeHints</structname>
structure for the named property and the specified window.
This is used by
<xref linkend='XGetNormalHints' xrefstyle='select: title'/>
and
<xref linkend='XGetZoomHints' xrefstyle='select: title'/>.
It also can be used to retrieve the value of any property of type
<property>WM_SIZE_HINTS</property>.
Thus, it may be useful if other properties of that type get defined.
<xref linkend='XGetSizeHints' xrefstyle='select: title'/>
returns a nonzero status if a size hint was defined
or zero otherwise.
</para>
<para>
<!-- .LP -->
<xref linkend='XGetSizeHints' xrefstyle='select: title'/>
can generate
<errorname>BadAtom</errorname>
and 
<errorname>BadWindow</errorname>
errors.
</para>
</sect2>
<sect2 id="Getting_and_Setting_an_XStandardColormap_Structure">
<title>Getting and Setting an XStandardColormap Structure</title>
<para>
To get the 
<structname>XStandardColormap</structname>
structure associated with one of the described atoms, use
<xref linkend='XGetStandardColormap' xrefstyle='select: title'/>.
This function has been superseded by
<xref linkend='XGetRGBColormaps' xrefstyle='select: title'/>.
</para>
<indexterm significance="preferred"><primary>XGetStandardColormap</primary></indexterm>
<!-- .sM -->
<funcsynopsis id='XGetStandardColormap'>
<funcprototype>
  <funcdef>Status <function>XGetStandardColormap</function></funcdef>
  <paramdef>Display<parameter> *display</parameter></paramdef>
  <paramdef>Window<parameter> w</parameter></paramdef>
  <paramdef>XStandardColormap<parameter> *colormap_return</parameter></paramdef>
  <paramdef>Atom<parameter> property</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<!-- .FN -->
<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies the connection to the X server.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the window.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>colormap_return</emphasis>
    </term>
    <listitem>
      <para>
Returns the colormap associated with the specified atom.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>property</emphasis>
    </term>
    <listitem>
      <para>
Specifies the property name.
    </para>
  </listitem>
  </varlistentry>
</variablelist>
<para>
<!-- .LP -->
<!-- .eM -->
The
<xref linkend='XGetStandardColormap' xrefstyle='select: title'/>
function returns the colormap definition associated with the atom supplied
as the property argument.
<xref linkend='XGetStandardColormap' xrefstyle='select: title'/>
returns a nonzero status if successful and zero otherwise.
For example,
to fetch the standard
<symbol>GrayScale</symbol>
colormap for a display,
you use
<xref linkend='XGetStandardColormap' xrefstyle='select: title'/>
with the following syntax:
<programlisting>
XGetStandardColormap(dpy, DefaultRootWindow(dpy), &amp;cmap, XA_RGB_GRAY_MAP);
</programlisting>
See <link linkend="Standard_Colormaps">section 14.3</link> for the
semantics of standard colormaps.
</para>
<para>
<!-- .LP -->
<xref linkend='XGetStandardColormap' xrefstyle='select: title'/>
can generate
<errorname>BadAtom</errorname>
and
<errorname>BadWindow</errorname>
errors.
</para>
<para>
<!-- .LP -->
<!-- .sp -->
To set a standard colormap, use
<xref linkend='XSetStandardColormap' xrefstyle='select: title'/>.
This function has been superseded by
<xref linkend='XSetRGBColormaps' xrefstyle='select: title'/>.
</para>
<indexterm significance="preferred"><primary>XSetStandardColormap</primary></indexterm>
<!-- .sM -->
<funcsynopsis id='XSetStandardColormap'>
<funcprototype>
  <funcdef><function>XSetStandardColormap</function></funcdef>
  <paramdef>Display<parameter> *display</parameter></paramdef>
  <paramdef>Window<parameter> w</parameter></paramdef>
  <paramdef>XStandardColormap<parameter> *colormap</parameter></paramdef>
  <paramdef>Atom<parameter> property</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<!-- .FN -->
<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies the connection to the X server.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the window.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>colormap</emphasis>
    </term>
    <listitem>
      <para>
Specifies the colormap.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>property</emphasis>
    </term>
    <listitem>
      <para>
Specifies the property name.
    </para>
  </listitem>
  </varlistentry>
</variablelist>
<para>
<!-- .LP -->
<!-- .eM -->
The
<xref linkend='XSetStandardColormap' xrefstyle='select: title'/>
function usually is only used by window or session managers.
</para>
<para>
<!-- .LP -->
<xref linkend='XSetStandardColormap' xrefstyle='select: title'/>
can generate
<errorname>BadAlloc</errorname>,
<errorname>BadAtom</errorname>,
<errorname>BadDrawable</errorname>,
and
<errorname>BadWindow</errorname>
errors.
</para>
</sect2>
<sect2 id="Parsing_Window_Geometry">
<title>Parsing Window Geometry</title>
<para>
To parse window geometry given a user-specified position 
and a default position, use
<xref linkend='XGeometry' xrefstyle='select: title'/>.
This function has been superseded by
<xref linkend='XWMGeometry' xrefstyle='select: title'/>.
</para>
<indexterm><primary>Window</primary><secondary>determining location</secondary></indexterm>
<indexterm significance="preferred"><primary>XGeometry</primary></indexterm>
<!-- .sM -->
<funcsynopsis id='XGeometry'>
<funcprototype>
  <funcdef>int <function>XGeometry</function></funcdef>
  <paramdef>Display<parameter> *display</parameter></paramdef>
  <paramdef>int<parameter> screen</parameter></paramdef>
  <paramdef>char*position,<parameter> *default_position</parameter></paramdef>
  <paramdef>unsignedint<parameter> bwidth</parameter></paramdef>
  <paramdef>unsignedintfwidth,<parameter> fheight</parameter></paramdef>
  <paramdef>intxadder,<parameter> yadder</parameter></paramdef>
  <paramdef>int*x_return,<parameter> *y_return</parameter></paramdef>
  <paramdef>int*width_return,<parameter> *height_return</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<!-- .FN -->
<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies the connection to the X server.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>screen</emphasis>
    </term>
    <listitem>
      <para>
Specifies the screen.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>position</emphasis>
    </term>
    <listitem>
      <para>
<!-- .br -->
<!-- .ns -->
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>default_position</emphasis>
    </term>
    <listitem>
      <para>
Specify the geometry specifications.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>bwidth</emphasis>
    </term>
    <listitem>
      <para>
Specifies the border width.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>fheight</emphasis>
    </term>
    <listitem>
      <para>
<!-- .br -->
<!-- .ns -->
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>fwidth</emphasis>
    </term>
    <listitem>
      <para>
Specify the font height and width in pixels (increment size).
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>xadder</emphasis>
    </term>
    <listitem>
      <para>
<!-- .br -->
<!-- .ns -->
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>yadder</emphasis>
    </term>
    <listitem>
      <para>
Specify additional interior padding needed in the window.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>x_return</emphasis>
    </term>
    <listitem>
      <para>
<!-- .br -->
<!-- .ns -->
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>y_return</emphasis>
    </term>
    <listitem>
      <para>
Return the x and y offsets.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>width_return</emphasis>
    </term>
    <listitem>
      <para>
<!-- .br -->
<!-- .ns -->
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>height_return</emphasis>
    </term>
    <listitem>
      <para>
Return the width and height determined.
    </para>
  </listitem>
  </varlistentry>
</variablelist>
<para>
<!-- .LP -->
<!-- .eM -->
You pass in the border width (bwidth),
size of the increments fwidth and fheight
(typically font width and height),
and any additional interior space (xadder and yadder)
to make it easy to compute the resulting size.
The
<xref linkend='XGeometry' xrefstyle='select: title'/>
function returns the position the window should be placed given a position and
a default position.
<xref linkend='XGeometry' xrefstyle='select: title'/>
determines the placement of
a window using a geometry specification as specified by
<xref linkend='XParseGeometry' xrefstyle='select: title'/>
and the additional information about the window.
Given a fully qualified default geometry specification and
an incomplete geometry specification, 
<xref linkend='XParseGeometry' xrefstyle='select: title'/>
returns a bitmask value as defined above in the 
<xref linkend='XParseGeometry' xrefstyle='select: title'/>
call,
by using the position argument.
</para>
<para>
<!-- .LP -->
The returned width and height will be the width and height specified
by default_position as overridden by any user-specified position.
They are not affected by fwidth, fheight, xadder, or yadder.
The x and y coordinates are computed by using the border width,
the screen width and height, padding as specified by xadder and yadder,
and the fheight and fwidth times the width and height from the
geometry specifications.
</para>
</sect2>
<sect2 id="Getting_the_X_Environment_Defaults">
<title>Getting the X Environment Defaults</title>
<para>
The
<xref linkend='XGetDefault' xrefstyle='select: title'/>
function provides a primitive interface to the resource manager facilities 
discussed in <link linkend='Resource_Manager_Functions'>chapter 15</link>.
It is only useful in very simple applications.
</para>
<!-- .LP -->
<!-- .sp -->
<indexterm significance="preferred"><primary>XGetDefault</primary></indexterm>
<!-- .sM -->
<funcsynopsis id='XGetDefault'>
<funcprototype>
  <funcdef>char *<function>XGetDefault</function></funcdef>
  <paramdef>Display<parameter> *display</parameter></paramdef>
  <paramdef>char<parameter> *program</parameter></paramdef>
  <paramdef>char<parameter> *option</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<!-- .FN -->
<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies the connection to the X server.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>program</emphasis>
    </term>
    <listitem>
      <para>
Specifies the program name for the Xlib defaults (usually argv[0] 
of the main program).
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>option</emphasis>
    </term>
    <listitem>
      <para>
Specifies the option name.
    </para>
  </listitem>
  </varlistentry>
</variablelist>
<para>
<!-- .LP -->
<!-- .eM -->
The
<xref linkend='XGetDefault' xrefstyle='select: title'/>
function returns the value of the resource <emphasis remap='I'>prog</emphasis>.<emphasis remap='I'>option</emphasis>,
where <emphasis remap='I'>prog</emphasis> is the program argument with the directory prefix removed
and <emphasis remap='I'>option</emphasis> must be a single component.
Note that multilevel resources cannot be used with
<xref linkend='XGetDefault' xrefstyle='select: title'/>.
The class "Program.Name" is always used for the resource lookup.
If the specified option name does not exist for this program,
<xref linkend='XGetDefault' xrefstyle='select: title'/>
returns NULL.
The strings returned by
<xref linkend='XGetDefault' xrefstyle='select: title'/>
are owned by Xlib and should not be modified or freed by the client.
</para>
<para>
<!-- .LP -->
If a database has been set with 
<xref linkend='XrmSetDatabase' xrefstyle='select: title'/>,
that database is used for the lookup.
Otherwise, a database is created
and is set in the display (as if by calling 
<xref linkend='XrmSetDatabase' xrefstyle='select: title'/>).
The database is created in the current locale.
To create a database,
<xref linkend='XGetDefault' xrefstyle='select: title'/>
uses resources from the RESOURCE_MANAGER property on the root
window of screen zero.
If no such property exists,
a resource file in the user's home directory is used.
On a <acronym>POSIX</acronym>-conformant system,
this file is
<function>"$HOME/.Xdefaults"</function>.
<indexterm><primary>Files</primary><secondary><filename>$HOME/.Xdefaults</filename></secondary></indexterm>
After loading these defaults,
<xref linkend='XGetDefault' xrefstyle='select: title'/>
merges additional defaults specified by the XENVIRONMENT
environment variable.
If XENVIRONMENT is defined,
it contains a full path name for the additional resource file.
If XENVIRONMENT is not defined,
<xref linkend='XGetDefault' xrefstyle='select: title'/>
looks for
"<filename>$HOME/.Xdefaults-<replaceable>name</replaceable></filename>" ,
where <replaceable>name</replaceable> specifies the name of the machine on which the application
is running.
</para>
</sect2>
</sect1>
<sect1 id="X_Version_10_Compatibility_Functions">
<title>X Version 10 Compatibility Functions</title>
<para>
You can use the X Version 10 compatibility functions to:
<itemizedlist>
  <listitem>
    <para>
Draw and fill polygons and curves
    </para>
  </listitem>
  <listitem>
    <para>
Associate user data with a value
    </para>
  </listitem>
</itemizedlist>
</para>
<sect2 id="Drawing_and_Filling_Polygons_and_Curves">
<title>Drawing and Filling Polygons and Curves</title>
<para>
<!-- .LP -->
Xlib provides functions that you can use to draw or fill
arbitrary polygons or curves.  
These functions are provided mainly for compatibility with X Version 10 
and have no server support.  
That is, they call other Xlib functions, not the server directly.  
Thus, if you just have straight lines to draw, using 
<xref linkend='XDrawLines' xrefstyle='select: title'/>
<indexterm><primary>XDrawLines</primary></indexterm>
or
<xref linkend='XDrawSegments' xrefstyle='select: title'/>
<indexterm><primary>XDrawSegments</primary></indexterm>
is much faster.
</para>
<para>
<!-- .LP -->
The functions discussed here provide all the functionality of the 
X Version 10 functions 
<xref linkend='XDraw' xrefstyle='select: title'/>,
<indexterm ><primary>X10 compatibility</primary><secondary>XDraw</secondary></indexterm>
<xref linkend='XDrawFilled' xrefstyle='select: title'/>,
<indexterm><primary>X10 compatibility</primary><secondary>XDrawFilled</secondary></indexterm>
<function>XDrawPatterned</function>,
<indexterm ><primary>X10 compatibility</primary><secondary>XDrawPatterned</secondary></indexterm>
<function>XDrawDashed</function>,
<indexterm><primary>X10 compatibility</primary><secondary>XDrawDashed</secondary></indexterm>
and
<function>XDrawTiled</function>.
<indexterm><primary>X10 compatibility</primary><secondary>XDrawTiled</secondary></indexterm>
They are as compatible as possible given X Version 11's new line-drawing 
functions.  
One thing to note, however, is that
<function>VertexDrawLastPoint</function>
is no longer supported. 
Also, the error status returned is the opposite of what it was under 
X Version 10 (this is the X Version 11 standard error status).  
<function>XAppendVertex</function>
and 
<function>XClearVertexFlag</function>
from X Version 10 also are not supported.
</para>
<para>
<!-- .LP -->
Just how the graphics context you use is set up actually
determines whether you get dashes or not, and so on.  
Lines are properly joined if they connect and include
the closing of a closed figure  (see 
<xref linkend='XDrawLines' xrefstyle='select: title'/>).
The functions discussed here fail (return zero) only if they run out of memory
or are passed a 
<structname>Vertex</structname>
list that has a 
<structname>Vertex</structname>
with 
<symbol>VertexStartClosed</symbol>
set that is not followed by a 
<structname>Vertex</structname>
with 
<symbol>VertexEndClosed</symbol>
set.
</para>
<para>
<!-- .LP -->
<!-- .sp -->
To achieve the effects of the X Version 10
<xref linkend='XDraw' xrefstyle='select: title'/>,
<indexterm ><primary>X10 compatibility</primary><secondary>XDraw</secondary></indexterm>
<function>XDrawDashed</function>,
<indexterm><primary>X10 compatibility</primary><secondary>XDrawDashed</secondary></indexterm>
and 
<function>XDrawPatterned</function>,
<indexterm ><primary>X10 compatibility</primary><secondary>XDrawPatterned</secondary></indexterm>
use
<xref linkend='XDraw' xrefstyle='select: title'/>.
</para>

<para>
#include &lt;X11/X10.h&gt;
</para>

<funcsynopsis id='XDraw'>
<funcprototype>
  <funcdef>Status <function>XDraw</function></funcdef>
  <paramdef>Display<parameter> *display</parameter></paramdef>
  <paramdef>Drawable<parameter> d</parameter></paramdef>
  <paramdef>GC<parameter> gc</parameter></paramdef>
  <paramdef>Vertex<parameter> *vlist</parameter></paramdef>
  <paramdef>int<parameter> vcount</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies the connection to the X server.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>d</emphasis>
    </term>
    <listitem>
      <para>
Specifies the drawable. 
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>gc</emphasis>
    </term>
    <listitem>
      <para>
Specifies the GC.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>vlist</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer to the list of vertices that indicate what to draw.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>vcount</emphasis>
    </term>
    <listitem>
      <para>
Specifies how many vertices are in vlist.
    </para>
  </listitem>
  </varlistentry>
</variablelist>
<para>
<!-- .LP -->
<!-- .eM -->
The
<xref linkend='XDraw' xrefstyle='select: title'/>
function draws an arbitrary polygon or curve.  
The figure drawn is defined by the specified list of vertices (vlist).
The points are connected by lines as specified in the flags in the
vertex structure.
</para>
<para>
<!-- .LP -->
Each Vertex, as defined in
<filename class="headerfile">&lt;X11/X10.h&gt;</filename>,
<indexterm type="file"><primary><filename class="headerfile">X11/X10.h</filename></primary></indexterm>
<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/X10.h&gt;</filename></secondary></indexterm>
<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/X10.h&gt;</filename></secondary></indexterm>
is a structure with the following members:
<indexterm significance="preferred"><primary>Vertex</primary></indexterm>
<synopsis>
typedef struct _Vertex {
	short x,y;
	unsigned short flags;
} Vertex;
</synopsis>
The x and y members are the coordinates of the vertex 
that are relative to either the upper left inside corner of the drawable 
(if 
<symbol>VertexRelative</symbol>
is zero) or the previous vertex (if 
<symbol>VertexRelative</symbol>
is one).
</para>
<para>
<!-- .LP -->
The flags, as defined in 
<filename class="headerfile">&lt;X11/X10.h&gt;</filename>,
<indexterm type="file"><primary><filename class="headerfile">X11/X10.h</filename></primary></indexterm>
<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/X10.h&gt;</filename></secondary></indexterm>
<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/X10.h&gt;</filename></secondary></indexterm>
are as follows:
<indexterm significance="preferred"><primary>VertexRelative</primary></indexterm>
<indexterm significance="preferred"><primary>VertexDontDraw</primary></indexterm>
<indexterm significance="preferred"><primary>VertexCurved</primary></indexterm>
<indexterm significance="preferred"><primary>VertexStartClosed</primary></indexterm>
<indexterm significance="preferred"><primary>VertexEndClosed</primary></indexterm>
<!-- .sM -->

<synopsis>
VertexRelative     0x0001     /* else absolute */
VertexDontDraw     0x0002     /* else draw */
VertexCurved       0x0004     /* else straight */
VertexStartClosed  0x0008     /* else not */
VertexEndClosed    0x0010     /* else not */
</synopsis>

<itemizedlist>
  <listitem>
    <para>
If 
<symbol>VertexRelative</symbol>
is not set,  
the coordinates are absolute (that is, relative to the drawable's origin).  
The first vertex must be an absolute vertex.
    </para>
  </listitem>
  <listitem>
    <para>
If
<symbol>VertexDontDraw</symbol>
is one, 
no line or curve is drawn from the previous vertex to this one.  
This is analogous to picking up the pen and moving to another place 
before drawing another line.
    </para>
  </listitem>
  <listitem>
    <para>
If 
<symbol>VertexCurved</symbol>
is one, 
a spline algorithm is used to draw a smooth curve from the previous vertex
through this one to the next vertex.  
Otherwise, a straight line is drawn from the previous vertex to this one.  
It makes sense to set 
<symbol>VertexCurved</symbol>
to one only if a previous and next vertex are both defined
(either explicitly in the array or through the definition of a closed 
curve).
    </para>
  </listitem>
  <listitem>
    <para>
It is permissible for 
<symbol>VertexDontDraw</symbol>
bits and 
<symbol>VertexCurved</symbol>
bits both to be one. 
This is useful if you want to define the previous point for the smooth curve
but do not want an actual curve drawing to start until this point.
    </para>
  </listitem>
  <listitem>
    <para>
If 
<symbol>VertexStartClosed</symbol>
is one, 
then this point marks the beginning of a closed curve.  
This vertex must be followed later in the array by another vertex 
whose effective coordinates are identical
and that has a
<symbol>VertexEndClosed</symbol>
bit of one.
The points in between form a cycle to determine predecessor 
and successor vertices for the spline algorithm.
    </para>
  </listitem>
</itemizedlist>
</para>
<para>
<!-- .LP -->
This function uses these GC components:
function, plane-mask, line-width, line-style, cap-style, join-style,
fill-style, subwindow-mode, clip-x-origin, clip-y-origin, and
clip-mask.
It also uses these GC mode-dependent components: 
foreground, background, tile, stipple,
tile-stipple-x-origin, tile-stipple-y-origin, dash-offset, and dash-list.
</para>
<para>
<!-- .LP -->
<!-- .sp -->
To achieve the effects of the X Version 10
<function>XDrawTiled</function>
<indexterm><primary>X10 compatibility</primary><secondary>XDrawTiled</secondary></indexterm>
and 
<xref linkend='XDrawFilled' xrefstyle='select: title'/>,
<indexterm><primary>X10 compatibility</primary><secondary>XDrawFilled</secondary></indexterm>
use
<xref linkend='XDrawFilled' xrefstyle='select: title'/>.
</para>

<para>#include &lt;X11/X10.h&gt;</para>

<funcsynopsis id='XDrawFilled'>
<funcprototype>
  <funcdef>Status <function>XDrawFilled</function></funcdef>
  <paramdef>Display<parameter> *display</parameter></paramdef>
  <paramdef>Drawable<parameter> d</parameter></paramdef>
  <paramdef>GC<parameter> gc</parameter></paramdef>
  <paramdef>Vertex<parameter> *vlist</parameter></paramdef>
  <paramdef>int<parameter> vcount</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<!-- .FN -->
<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies the connection to the X server.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>d</emphasis>
    </term>
    <listitem>
      <para>
Specifies the drawable. 
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>gc</emphasis>
    </term>
    <listitem>
      <para>
Specifies the GC.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>vlist</emphasis>
    </term>
    <listitem>
      <para>
Specifies a pointer to the list of vertices that indicate what to draw.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>vcount</emphasis>
    </term>
    <listitem>
      <para>
Specifies how many vertices are in vlist.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
<!-- .LP -->
<!-- .eM -->
The
<xref linkend='XDrawFilled' xrefstyle='select: title'/>
function draws arbitrary polygons or curves and then fills them.
</para>
<para>
<!-- .LP -->
This function uses these GC components:
function, plane-mask, line-width, line-style, cap-style, join-style,
fill-style, subwindow-mode, clip-x-origin, clip-y-origin, and
clip-mask.
It also uses these GC mode-dependent components: 
foreground, background, tile, stipple,
tile-stipple-x-origin, tile-stipple-y-origin, 
dash-offset, dash-list, fill-style, and fill-rule.
</para>
</sect2>
<sect2 id="Associating_User_Data_with_a_Value">
<title>Associating User Data with a Value</title>
<para>
<!-- .LP -->
These functions have been superseded by the context management functions
(see <link linkend="Using_the_Context_Manager">section 16.10</link>).
It is often necessary to associate arbitrary information with resource IDs.
Xlib provides the 
<function>XAssocTable</function>
functions that you can use to make such an association.
<indexterm><primary>Hash Lookup</primary></indexterm>
<indexterm><primary>Window</primary><secondary>IDs</secondary></indexterm>
<indexterm><primary>Resource IDs</primary></indexterm>
Application programs often need to be able to easily refer to
their own data structures when an event arrives.
The 
<function>XAssocTable</function>
system provides users of the X library with a method
for associating their own data structures with X resources
(<type>Pixmap</type>s,
<type>Font</type>s,
<type>Window</type>s,
and so on).
</para>
<para>
<!-- .LP -->
An 
<function>XAssocTable</function>
can be used to type X resources.  
For example, the user
may want to have three or four types of windows,
each with different properties. 
This can be accomplished by associating each X window ID
with a pointer to a window property data structure  defined  by  the
user.
A generic type has been defined in the X library for resource IDs.
It is called an XID.
</para>
<para>
<!-- .LP -->
There are a few  guidelines  that  should be observed when using an
<function>XAssocTable</function> :
</para>
<itemizedlist>
  <listitem>
    <para>
All  XIDs  are  relative  to  the  specified display.
    </para>
  </listitem>
  <listitem>
    <para>
Because  of  the  hashing  scheme  used  by  the  association mechanism,
the following rules for determining the size of a
<function>XAssocTable</function>
should be followed.  
Associations will be  made  and  looked  up  more
efficiently  if  the  table  size  (number  of  buckets in the hashing
system) is a power of two and if there are not more than 8 XIDs  per
bucket.
    </para>
  </listitem>
</itemizedlist>

<para>
<!-- .LP -->
<!-- .sp -->
To return a pointer to a new
<function>XAssocTable</function>,
use 
<xref linkend='XCreateAssocTable' xrefstyle='select: title'/>.
<indexterm significance="preferred"><primary>XCreateAssocTable</primary></indexterm>
<!-- .sM -->
</para>
<funcsynopsis id='XCreateAssocTable'>
<funcprototype>
  <funcdef>XAssocTable *<function>XCreateAssocTable</function></funcdef>
  <paramdef>int<parameter> size</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<!-- .FN -->
<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>size</emphasis>
    </term>
    <listitem>
      <para>
Specifies the number of buckets in the hash system of
<function>XAssocTable</function>.
    </para>
  </listitem>
  </varlistentry>
</variablelist>

<para>
<!-- .LP -->
<!-- .eM -->
The size argument specifies the number of buckets in the 
hash system of
<function>XAssocTable</function>.
For  reasons  of  efficiency  the number of buckets
should be a power of two.
Some size  suggestions  might  be:  use  32 buckets  per  100  objects,
and a reasonable maximum number of objects per buckets is 8.
If  an  error  allocating  memory  for  the
<function>XAssocTable</function>
occurs, 
a NULL pointer is returned. 
</para>
<para>
<!-- .LP -->
<!-- .sp -->
To create an entry in a given 
<function>XAssocTable</function>,
use 
<xref linkend='XMakeAssoc' xrefstyle='select: title'/>.
<indexterm significance="preferred"><primary>XMakeAssoc</primary></indexterm>
<!-- .sM -->
</para>
<funcsynopsis id='XMakeAssoc'>
<funcprototype>
  <funcdef><function>XMakeAssoc</function></funcdef>
  <paramdef>Display<parameter> *display</parameter></paramdef>
  <paramdef>XAssocTable<parameter> *table</parameter></paramdef>
  <paramdef>XID<parameter> x_id</parameter></paramdef>
  <paramdef>char<parameter> *data</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<!-- .FN -->
<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies the connection to the X server.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>table</emphasis>
    </term>
    <listitem>
      <para>
Specifies the assoc table. 
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>x_id</emphasis>
    </term>
    <listitem>
      <para>
Specifies the X resource ID.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>data</emphasis>
    </term>
    <listitem>
      <para>
Specifies the data to be associated with the X resource ID.
    </para>
  </listitem>
  </varlistentry>
</variablelist>
<para>
<!-- .LP -->
<!-- .eM -->
The
<xref linkend='XMakeAssoc' xrefstyle='select: title'/>
function inserts data into an 
<function>XAssocTable</function>
keyed on an XID.
Data is inserted into the table only once.
Redundant inserts are ignored.
The queue in each association bucket is sorted from the lowest XID to 
the highest XID.
</para>
<para>
<!-- .LP -->
<!-- .sp -->
To obtain data from a given 
<function>XAssocTable</function>,
use 
<xref linkend='XLookUpAssoc' xrefstyle='select: title'/>.
</para>
<indexterm significance="preferred"><primary>XLookUpAssoc</primary></indexterm>
<!-- .sM -->
<funcsynopsis id='XLookUpAssoc'>
<funcprototype>
  <funcdef>char *<function>XLookUpAssoc</function></funcdef>
  <paramdef>Display<parameter> *display</parameter></paramdef>
  <paramdef>XAssocTable<parameter> *table</parameter></paramdef>
  <paramdef>XID<parameter> x_id</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<!-- .FN -->
<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies the connection to the X server.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>table</emphasis>
    </term>
    <listitem>
      <para>
Specifies the assoc table. 
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>x_id</emphasis>
    </term>
    <listitem>
      <para>
Specifies the X resource ID.
    </para>
  </listitem>
  </varlistentry>
</variablelist>
<para>
<!-- .LP -->
<!-- .eM -->
The
<xref linkend='XLookUpAssoc' xrefstyle='select: title'/>
function retrieves the data stored in an 
<function>XAssocTable</function>
by its XID.  
If  an appropriately  matching XID can be found in the table,
<xref linkend='XLookUpAssoc' xrefstyle='select: title'/>
returns the data associated with it.
If the x_id cannot be found in the table,
it returns NULL.
</para>
<para>
<!-- .LP -->
<!-- .sp -->
To delete an entry from a given 
<function>XAssocTable</function>,
use 
<xref linkend='XDeleteAssoc' xrefstyle='select: title'/>.
</para>
<indexterm significance="preferred"><primary>XDeleteAssoc</primary></indexterm>
<!-- .sM -->
<funcsynopsis id='XDeleteAssoc'>
<funcprototype>
  <funcdef><function>XDeleteAssoc</function></funcdef>
  <paramdef>Display<parameter> *display</parameter></paramdef>
  <paramdef>XAssocTable<parameter> *table</parameter></paramdef>
  <paramdef>XID<parameter> x_id</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<!-- .FN -->
<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>display</emphasis>
    </term>
    <listitem>
      <para>
Specifies the connection to the X server.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>table</emphasis>
    </term>
    <listitem>
      <para>
Specifies the assoc table. 
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>x_id</emphasis>
    </term>
    <listitem>
      <para>
Specifies the X resource ID.
    </para>
  </listitem>
  </varlistentry>
</variablelist>
<para>
<!-- .LP -->
<!-- .eM -->
The
<xref linkend='XDeleteAssoc' xrefstyle='select: title'/>
function deletes an association in an 
<function>XAssocTable</function>
keyed on its XID.
Redundant deletes (and deletes of nonexistent XIDs) are ignored.
Deleting associations in no way impairs the performance of an
<function>XAssocTable</function>.
</para>
<para>
<!-- .LP -->
<!-- .sp -->
To free the memory associated with a given 
<function>XAssocTable</function>,
use 
<xref linkend='XDestroyAssocTable' xrefstyle='select: title'/>.
</para>
<indexterm significance="preferred"><primary>XDestroyAssocTable</primary></indexterm>
<!-- .sM -->
<funcsynopsis id='XDestroyAssocTable'>
<funcprototype>
  <funcdef><function>XDestroyAssocTable</function></funcdef>
  <paramdef>XAssocTable<parameter> *table</parameter></paramdef>
</funcprototype>
</funcsynopsis>

<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>table</emphasis>
    </term>
    <listitem>
      <para>
Specifies the assoc table. 
    </para>
  </listitem>
  </varlistentry>
</variablelist>
</sect2>
</sect1>
</appendix>
