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      <div xmlns="" class="refnamediv">
        <a xmlns="http://www.w3.org/1999/xhtml" id="clCreateContext"></a>
        <h1>clCreateContext</h1>
        <p>Creates an OpenCL context.</p>
      </div>
      <div class="refsynopsisdiv">
        <h2></h2>
        <div class="funcsynopsis">
          <table xmlns="" border="0" summary="Function synopsis" cellspacing="0" cellpadding="0">
            <tr valign="bottom">
              <td>
                <code xmlns="http://www.w3.org/1999/xhtml" class="funcdef"><a class="link" href="abstractDataTypes.html" target="pagedisplay">cl_context</a> <strong class="fsfunc">clCreateContext</strong>(</code>
                <td>const <a xmlns="http://www.w3.org/1999/xhtml" class="link" href="enums.html#cl_context_properties" target="pagedisplay">cl_context_properties</a> <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">*properties</var>, </td>
              </td>
            </tr>
            <tr valign="top">
              <td> </td>
              <td><a xmlns="http://www.w3.org/1999/xhtml" class="link" href="scalarDataTypes.html" target="pagedisplay">cl_uint</a> <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">num_devices</var>, </td>
            </tr>
            <tr valign="top">
              <td> </td>
              <td>const <a xmlns="http://www.w3.org/1999/xhtml" class="link" href="abstractDataTypes.html" target="pagedisplay">cl_device_id</a> <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">*devices</var>, </td>
            </tr>
            <tr valign="top">
              <td> </td>
              <td><a xmlns="http://www.w3.org/1999/xhtml" class="link" href="scalarDataTypes.html" target="pagedisplay">(void</a> CL_CALLBACK  <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">*pfn_notify)</var>
                        <code xmlns="http://www.w3.org/1999/xhtml">(</code><div xmlns="http://www.w3.org/1999/xhtml" class="literallayout"><p>const <a class="link" href="scalarDataTypes.html" target="pagedisplay">char</a> *errinfo,<br />
                        const <a class="link" href="scalarDataTypes.html" target="pagedisplay">void</a> *private_info, <a class="link" href="otherDataTypes.html" target="_top">size_t</a> cb,<br />
                        <a class="link" href="scalarDataTypes.html" target="pagedisplay">void</a> *user_data</p></div><code xmlns="http://www.w3.org/1999/xhtml">)</code>, </td>
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              <td> </td>
              <td><a xmlns="http://www.w3.org/1999/xhtml" class="link" href="scalarDataTypes.html" target="pagedisplay">void</a> <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">*user_data</var>, </td>
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            <tr valign="top">
              <td> </td>
              <td><a xmlns="http://www.w3.org/1999/xhtml" class="link" href="scalarDataTypes.html" target="pagedisplay">cl_int</a> <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">*errcode_ret</var><code>)</code></td>
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      </div>
      <div class="refsect1">
        <a id="description"></a>
        <h2>Description</h2>
        <p>
          An OpenCL context is created with one or more devices. Contexts are used by the
          OpenCL runtime for managing objects such as command-queues, memory, program and kernel
          objects and for executing kernels on one or more devices specified in the context.
        </p>
      </div>
      <div class="refsect1">
        <a id="parameters"></a>
        <h2>Parameters</h2>
        <div class="variablelist">
          <dl class="variablelist">
            <dt>
              <span class="term">properties</span>
            </dt>
            <dd>
              <p>
                   Specifies a list of context property names and
                  their corresponding values. Each property name is immediately followed
                  by the corresponding desired value. The list is terminated with 0.
                  <code class="varname">properties</code> can be NULL in which case the platform
                  that is selected is implementation-defined. The list of supported
                  <code class="varname">properties</code> is described in the table below.
                </p>
              <p>
                   If the extension
                  <a class="citerefentry" href="cl_khr_dx9_media_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_dx9_media_sharing</span></span></a>
                  is enabled, then <code class="varname">properties</code> specifies a list of context
                  property names and their corresponding values. Each property is followed
                  immediately by the corresponding desired value. The list is terminated with
                  zero. If a property is not specified in <code class="varname">properties</code>, then its
                  default value (listed in the table below) is used (it is said to be specified
                  implicitly).  If <code class="varname">properties</code> is NULL or empty (points to
                  a list whose first value is zero), all attributes take on their default values.
                </p>
              <p>
                  If the extension
                  <a class="citerefentry" href="cl_khr_d3d10_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_d3d10_sharing</span></span></a>
                  is enabled, then <code class="varname">properties</code> specifies a list of context
                  property names and their corresponding values.  Each property is followed
                  immediately by the corresponding desired value.  The list is terminated
                  with zero.  if a property is not specified in <code class="varname">properties</code>,
                  then its default value is used (it is said to be specified implicitly). If
                  <code class="varname">properties</code> is NULL or empty (points to a list whose first
                  value is zero), all attributes take on their default value.
                </p>
              <p>
                  If the extension
                  <a class="citerefentry" href="cl_khr_gl_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_gl_sharing</span></span></a>
                  is enabled, then <code class="varname">properties</code> points to an attribute list,
                  which is a array of ordered &lt;attribute name, value&gt; pairs terminated with
                  zero. If an attribute is not specified in <code class="varname">properties</code>,
                  then its default value is used (it is said to be specified implicitly). If
                  <code class="varname">properties</code> is NULL or empty (points to a list whose first
                  value is zero), all attributes take on their default values..
                </p>
              <div class="informaltable">
                <table border="1">
                  <colgroup>
                    <col align="left" class="col1" />
                    <col align="left" class="col2" />
                    <col align="left" class="col3" />
                  </colgroup>
                  <thead>
                    <tr>
                      <th align="left">cl_context_properties enum</th>
                      <th align="left">Property value</th>
                      <th align="left">Description</th>
                    </tr>
                  </thead>
                  <tbody>
                    <tr>
                      <td align="left">
                        <code class="constant">CL_CONTEXT_PLATFORM</code>
                      </td>
                      <td align="left">
                        <a class="link" href="abstractDataTypes.html" target="pagedisplay">cl_platform_id</a>
                      </td>
                      <td align="left">Specifies the platform to use.</td>
                    </tr>
                    <tr>
                      <td align="left">
                        <code class="constant">CL_CONTEXT_INTEROP_USER_SYNC</code>
                      </td>
                      <td align="left">
                        <a class="link" href="enums.html#cl_bool" target="pagedisplay">cl_bool</a>
                      </td>
                      <td align="left">
                                Specifies whether the user is responsible for synchronization between OpenCL
                                and other APIs. Please refer to the specific sections in the OpenCL 1.2 extension specification
                                that describe sharing with other APIs for restrictions on using this flag.

                                <p>
                                  If <code class="constant">CL_CONTEXT_INTEROP_USER_</code> SYNC is not
                                  specified, a default of <code class="constant">CL_FALSE</code> is assumed.
                                </p>
                            </td>
                    </tr>
                    <tr>
                      <td align="left">
                        <code class="constant">CL_CONTEXT_D3D10_DEVICE_KHR</code>
                      </td>
                      <td align="left">ID3D10Device*</td>
                      <td align="left">
                              If the
                              <a class="citerefentry" href="cl_khr_d3d10_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_d3d10_sharing</span></span></a>
                              extension is enabled, specifies the <span class="type">ID3D10Device</span>*
                              to use for Direct3D 10 interoperability. The default value is NULL.
                            </td>
                    </tr>
                    <tr>
                      <td align="left">
                        <code class="constant">CL_GL_CONTEXT_KHR</code>
                      </td>
                      <td align="left">0, OpenGL context handle</td>
                      <td align="left">
                              OpenGL context to associated
                              the OpenCL context with (available if the
                              <a class="citerefentry" href="cl_khr_gl_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_gl_sharing</span></span></a>
                              extension is enabled)
                            </td>
                    </tr>
                    <tr>
                      <td align="left">
                        <code class="constant">CL_EGL_DISPLAY_KHR</code>
                      </td>
                      <td align="left"> <code class="constant">EGL_NO_DISPLAY</code>, <span class="type">EGLDisplay</span> handle </td>
                      <td align="left">
                              EGLDisplay an OpenGL context was
                              created with respect to (available if the
                              <a class="citerefentry" href="cl_khr_gl_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_gl_sharing</span></span></a>
                              extension is enabled)
                            </td>
                    </tr>
                    <tr>
                      <td align="left">
                        <code class="constant">CL_GLX_DISPLAY_KHR</code>
                      </td>
                      <td align="left">None, X handle</td>
                      <td align="left">
                              X Display an OpenGL context was
                              created with respect to (available if the
                              <a class="citerefentry" href="cl_khr_gl_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_gl_sharing</span></span></a>
                              extension is enabled)
                            </td>
                    </tr>
                    <tr>
                      <td align="left">
                        <code class="constant">CL_CGL_SHAREGROUP_KHR</code>
                      </td>
                      <td align="left">0, CGL share group handle</td>
                      <td align="left">
                              CGL share group to associate the OpenCL context with (available if the
                              <a class="citerefentry" href="cl_khr_gl_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_gl_sharing</span></span></a>
                              extension is enabled)
                            </td>
                    </tr>
                    <tr>
                      <td align="left">
                        <code class="constant">CL_WGL_HDC_KHR</code>
                      </td>
                      <td align="left">0, HDC handle</td>
                      <td align="left">
                              HDC an OpenGL context was created with respect to (available if the
                              <a class="citerefentry" href="cl_khr_gl_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_gl_sharing</span></span></a>
                              extension is enabled)
                            </td>
                    </tr>
                    <tr>
                      <td align="left">
                        <code class="constant">CL_CONTEXT_ADAPTER_D3D9_KHR</code>
                      </td>
                      <td align="left">IDirect3DDevice9 *</td>
                      <td align="left">
                              Specifies an <span class="type">IDirect3DDevice9</span>
                              to use for D3D9 interop (if the
                              <a class="citerefentry" href="cl_khr_dx9_media_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_dx9_media_sharing</span></span></a>
                              extension is supported).
                            </td>
                    </tr>
                    <tr>
                      <td align="left">
                        <code class="constant">CL_CONTEXT_ADAPTER_D3D9EX_KHR</code>
                      </td>
                      <td align="left">IDirect3DDeviceEx*</td>
                      <td align="left">
                              Specifies an <span class="type">IDirect3DDevice9Ex</span>
                              to use for D3D9 interop (if the
                              <a class="citerefentry" href="cl_khr_dx9_media_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_dx9_media_sharing</span></span></a>
                              extension is supported).
                            </td>
                    </tr>
                    <tr>
                      <td align="left">
                        <code class="constant">CL_CONTEXT_ADAPTER_DXVA_KHR</code>
                      </td>
                      <td align="left">IDXVAHD_Device *</td>
                      <td align="left">
                              Specifies an <span class="type">IDXVAHD_Device</span>
                              to use for DXVA interop (if the
                              <a class="citerefentry" href="cl_khr_dx9_media_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_dx9_media_sharing</span></span></a>
                              extension is supported).
                            </td>
                    </tr>
                    <tr>
                      <td align="left">
                        <code class="constant">CL_CONTEXT_D3D11_DEVICE_KHR</code>
                      </td>
                      <td align="left">ID3D11Device *</td>
                      <td align="left">
                              Specifies the <span class="type">ID3D11Device</span> * to use for Direct3D 11
                              interoperability. The default value is NULL.
                            </td>
                    </tr>
                  </tbody>
                </table>
              </div>
            </dd>
            <dt>
              <span class="term">
                <code class="varname">num_devices</code>
              </span>
            </dt>
            <dd>
              <p>
                    The number of devices specified in the <code class="varname">devices</code> argument.
                </p>
            </dd>
            <dt>
              <span class="term">
                <code class="varname">devices</code>
              </span>
            </dt>
            <dd>
              <p>
                  A pointer to a list of unique devices returned by
                  <a class="citerefentry" href="clGetDeviceIDs.html"><span class="citerefentry"><span class="refentrytitle">clGetDeviceIDs</span></span></a>
                  or sub-devices created by
                  <a class="citerefentry" href="clCreateSubDevices.html"><span class="citerefentry"><span class="refentrytitle">clCreateSubDevices</span></span></a>
                  for a platform.
                </p>
            </dd>
            <dt>
              <span class="term">
                <code class="varname">pfn_notify</code>
              </span>
            </dt>
            <dd>
              <p>
                  A callback function that can be registered by the application. This callback
                  function will be used by the OpenCL implementation to report information
                  on errors during context creation as well as errors that occur at runtime
                  in this context.  This callback function may be called asynchronously by
                  the OpenCL implementation.  It is the application's responsibility to ensure
                  that the callback function is thread-safe. If <code class="varname">pfn_notify</code>
                  is NULL, no callback function is registered.  The parameters to this callback
                  function are:
                </p>
              <p><code class="varname">errinfo</code> is a pointer to an error string.</p>
              <p>
                  <code class="varname">private_info</code> and <code class="varname">cb</code> represent a pointer
                  to binary data that is returned by the OpenCL implementation that can be used
                  to log additional information helpful in debugging the error.
                </p>
              <p><code class="varname">user_data</code> is a pointer to user supplied data.</p>
              <p>
                  NOTE: There are a number of cases where error notifications need to be
                  delivered due to an error that occurs outside a context. Such notifications
                  may not be delivered through the <code class="varname">pfn_notify</code> callback. Where
                  these notifications go is implementation-defined.
                </p>
            </dd>
            <dt>
              <span class="term">
                <code class="varname">user_data</code>
              </span>
            </dt>
            <dd>
              <p>
                  Passed as the <code class="varname">user_data</code> argument when
                  <code class="varname">pfn_notify</code> is called. <code class="varname">user_data</code> can
                  be NULL.
                </p>
            </dd>
            <dt>
              <span class="term">
                <code class="varname">errcode_ret</code>
              </span>
            </dt>
            <dd>
              <p>
                  Returns an appropriate error code. If <code class="varname">errcode_ret</code> is NULL,
                  no error code is returned.
                </p>
            </dd>
          </dl>
        </div>
      </div>
      <div class="refsect1">
        <a id="notes"></a>
        <h2>Notes</h2>
        <p>
          <code class="function">clCreateContext</code> and
          <a class="citerefentry" href="clCreateContextFromType.html"><span class="citerefentry"><span class="refentrytitle">clCreateContextFromType</span></span></a>
          perform an implicit retain. This is very helpful for 3rd party libraries, which
          typically get a context passed to them by the application.  However, it is possible
          that the application may delete the context without informing the library.  Allowing
          functions to attach to (i.e. retain) and release a context solves the problem of a
          context being used by a library no longer being valid.
        </p>
      </div>
      <div class="refsect1">
        <a id="errors"></a>
        <h2>Errors</h2>
        <p>
        <code class="function">clCreateContext</code> returns a valid non-zero context and
        <code class="varname">errcode_ret</code> is set to <span class="errorname">CL_SUCCESS</span> if the
        context is created  successfully. Otherwise, it returns NULL value with the following
        error values returned in <code class="varname">errcode_ret</code>:
      </p>
        <div class="itemizedlist">
          <ul class="itemizedlist" style="list-style-type: disc; ">
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_PLATFORM</span> if <code class="varname">properties</code>
          is NULL and no platform could be selected or if platform value specified
          in <code class="varname">properties</code> is not a valid platform. (If the extension
          <a class="citerefentry" href="cl_khr_gl_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_gl_sharing</span></span></a>
          is enabled, then this error is replaced with
          <code class="constant">CL_INVALID_GL_SHAREGROUP_REFERENCE_KHR</code>; see below.)
        </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_PROPERTY</span> if context property name in
          <code class="varname">properties</code> is not a supported property name, if the
          value specified for a supported property name is not valid, or if the
          same property name is specified more than once. However if the extension
          <a class="citerefentry" href="cl_khr_gl_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_gl_sharing</span></span></a> is
          enabled, then <code class="constant">CL_INVALID_PROPERTY</code> is returned if an attribute
          name other than those listed in the table for <code class="varname">properties</code>
          above or if <code class="constant">CL_CONTEXT_INTEROP_USER_SYNC</code> is specified in
          <code class="varname">properties</code>.
        </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_PROPERTY</span> if an attribute name other than those
          specified in table 4.5 or if <code class="constant">CL_CONTEXT_INTEROP_USER_SYNC</code> is
          specified in properties.
        </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_VALUE</span> if <code class="varname">devices</code> is NULL; if
          <code class="varname">num_devices</code> is equal to zero; or if <code class="varname">pfn_notify</code>
          is NULL but <code class="varname">user_data</code> is not NULL.
        </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_DEVICE</span> if <code class="varname">devices</code> contains an invalid device.
        </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_OPERATION</span> if Direct3D 10 interoperability is
          specified by setting <code class="constant">CL_INVALID_D3D10_DEVICE_KHR</code> to a non-NULL
          value, and interoperability with another graphics API is also specified (if the
          <a class="citerefentry" href="cl_khr_d3d10_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_d3d10_sharing</span></span></a>
          extension is enabled).
        </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_DEVICE_NOT_AVAILABLE</span> if a device in <code class="varname">devices</code>
          is currently not available even though the device was returned by
          <a class="citerefentry" href="clGetDeviceIDs.html"><span class="citerefentry"><span class="refentrytitle">clGetDeviceIDs</span></span></a>.
        </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_OUT_OF_RESOURCES</span> if there is a failure to allocate resources
          required by the OpenCL implementation on the device.
        </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_OUT_OF_HOST_MEMORY</span> if there is a failure to allocate
          resources required by the OpenCL implementation on the host.
        </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_D3D10_DEVICE_KHR</span> if the Direct3D
          10 device specified for interoperability is not compatible with
          the devices against which the context is to be created (if the
          <a class="citerefentry" href="cl_khr_d3d10_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_d3d10_sharing</span></span></a>
          extension is enabled).
        </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_D3D10_DEVICE_KHR</span> if the value of the property
          <code class="constant">CL_CONTEXT_D3D10_DEVICE_KHR</code> is non-NULL and does not specify
          a valid Direct3D 10 device with which the <code class="varname">cl_device_ids</code>
          against which this context is to be created may interoperate (if the
          <a class="citerefentry" href="cl_khr_d3d10_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_d3d10_sharing</span></span></a>
          extension is enabled).
        </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_GL_SHAREGROUP_REFERENCE_KHR</span> when an invalid OpenGL
          context or share group object handle is specified in <code class="varname">properties</code> (only
          if the <a class="citerefentry" href="cl_khr_gl_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_gl_sharing</span></span></a>
          extension is enabled).
        </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_GL_SHAREGROUP_REFERENCE_KHR</span> if no OpenGL or
          OpenGL ES context or share group is specified in the attribute list given to
          <a class="citerefentry" href="clCreateContext.html"><span class="citerefentry"><span class="refentrytitle">clCreateContext</span></span></a>
          and any of the commands in section 9.7 are called. (if the
          <a class="citerefentry" href="cl_khr_gl_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_gl_sharing</span></span></a> extension
          is enabled)
        </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_GL_SHAREGROUP_REFERENCE_KHR</span> if the
            <a class="citerefentry" href="cl_khr_gl_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_gl_sharing</span></span></a>
            extension is enabled and if a context was specified by any of the following means:

            <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem" style="list-style-type: disc">
                  A context specified for an EGL-based OpenGL ES or OpenGL implementation
                  by setting the attributes <code class="constant">CL_GL_CONTEXT_KHR</code> and
                  <code class="constant">CL_EGL_DISPLAY_KHR</code>.
                </li><li class="listitem" style="list-style-type: disc">
                  A context was specified for a GLX-based OpenGL implementation by
                  setting the attributes <code class="constant">CL_GL_CONTEXT_KHR</code> and
                  <code class="constant">CL_GLX_DISPLAY_KHR</code>.
                </li><li class="listitem" style="list-style-type: disc">
                  A context was specified for a WGL-based OpenGL implementation by
                  setting the attributes <code class="constant">CL_GL_CONTEXT_KHR</code> and
                  <code class="constant">CL_WGL_HDC_KHR</code>.
                </li></ul></div>

            and any of the following conditions hold:

            <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem" style="list-style-type: disc">
                  The specified display and context attributes do not identify a valid
                  OpenGL or OpenGL ES context.
                </li><li class="listitem" style="list-style-type: disc">
                   The specified context does not support buffer and renderbuffer objects.
                </li><li class="listitem" style="list-style-type: disc">
                  The specified context is not compatible with the OpenCL context being
                  created (for example, it exists in a physically distinct address space,
                  such as another hardware device, or does not support sharing data with
                  OpenCL due to implementation restrictions).
                </li></ul></div></li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_GL_SHAREGROUP_REFERENCE_KHR</span> if a
          share group was specified for a CGL-based OpenGL implementation by
          setting the attribute <code class="constant">CL_CGL_SHAREGROUP_KHR</code>, and the
          specified share group does not identify a valid CGL share group object (if the
          <a class="citerefentry" href="cl_khr_gl_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_gl_sharing</span></span></a> extension
          is enabled).
        </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_OPERATION</span> if a context was specified as described above 
            and any of the following conditions hold:

            <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem" style="list-style-type: disc">
                  A context or share group object was specified for one of CGL, EGL, GLX, or WGL
                  and the OpenGL implementation does not support that window-system binding API.
                </li><li class="listitem" style="list-style-type: disc">
                  More than one of the attributes <code class="constant">CL_CGL_SHAREGROUP_KHR</code>,
                  <code class="constant">CL_EGL_DISPLAY_KHR</code>, <code class="constant">CL_GLX_DISPLAY_KHR</code>,
                  and <code class="constant">CL_WGL_HDC_KHR</code> is set to a non-default value.
                </li><li class="listitem" style="list-style-type: disc">
                  Both of the attributes <code class="constant">CL_CGL_SHAREGROUP_KHR</code> and
                  <code class="constant">CL_GL_CONTEXT_KHR</code> are set to non-default values.
                </li><li class="listitem" style="list-style-type: disc">
                  Any of the devices specified in the devices argument cannot support OpenCL
                  objects which share the data store of an OpenGL object, as described in
                  section 9.7.
                </li></ul></div></li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_DX9_MEDIA_ADAPTER_KHR</span> if the
          media adapter specified for interoperability is not compatible with
          the devices against which the context is to be created (only if the
          <a class="citerefentry" href="cl_khr_dx9_media_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_dx9_media_sharing</span></span></a>
          extension is supported).
        </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_ADAPTER_KHR</span> if
          any of the values of the properties <code class="constant">CL_CONTEXT_ADAPTER_D3D9_KHR</code>,
          <code class="constant">CL_CONTEXT_ADAPTER_D3D9EX_KHR</code> or
          <code class="constant">CL_CONTEXT_ADAPTER_DXVA_KHR</code> is non-NULL and
          does not specify a valid media adapter with which the cl_device_ids
          against which this context  is to be created may interoperate (only if the
          <a class="citerefentry" href="cl_khr_dx9_media_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_dx9_media_sharing</span></span></a>
          extension is supported).
        </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_OPERATION</span> if interoperability is
          specified by setting <code class="constant">CL_CONTEXT_ADAPTER_D3D9_KHR</code>,
          <code class="constant">CL_CONTEXT_ADAPTER_D3D9EX_KHR</code> or
          <code class="constant">CL_CONTEXT_ADAPTER_DXVA_KHR</code> to a non-NULL value, and
          interoperability with another graphics API is also specified (only if the
          <a class="citerefentry" href="cl_khr_dx9_media_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_dx9_media_sharing</span></span></a>
          extension is supported).
        </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_OPERATION</span>
          if Direct3D 11 interoperability is specified by setting
          <code class="constant">CL_INVALID_D3D11_DEVICE_KHR</code> to a non-NULL value, and
          interoperability with another graphics API is also specified (only if the
          <a class="citerefentry" href="cl_khr_d3d11_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_d3d11_sharing</span></span></a>
          extension is supported).
        </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_D3D11_DEVICE_KHR</span> if the value of the property
          <code class="constant">CL_CONTEXT_D3D11_DEVICE_KHR</code> is non-NULL and does not specify
          a valid Direct3D 11 device with which the <code class="varname">cl_device_ids</code>
          against which this context is to be created may interoperate (only if the
          <a class="citerefentry" href="cl_khr_d3d11_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_d3d11_sharing</span></span></a>
          extension is supported).
        </li>
            <li class="listitem" style="list-style-type: disc"><span class="errorname">CL_INVALID_D3D11_DEVICE_KHR</span> if the Direct3D
          11 device specified for interoperability is not compatible with
          the devices against which the context is to be created (only if the
          <a class="citerefentry" href="cl_khr_d3d11_sharing.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_d3d11_sharing</span></span></a>
          extension is supported).
        </li>
          </ul>
        </div>
      </div>
      <div class="refsect1">
        <a id="specification"></a>
        <h2>Specification</h2>
        <p><img src="pdficon_small1.gif" />
            <a href="http://www.khronos.org/registry/cl/specs/opencl-1.2.pdf#page=54" target="OpenCL Spec">OpenCL Specification</a>
        </p>
      </div>
      <div class="refsect1">
        <a id="seealso"></a>
        <h2>Also see</h2>
        <p>
            <a class="citerefentry" href="clGetDeviceIDs.html"><span class="citerefentry"><span class="refentrytitle">clGetDeviceIDs</span></span></a>,
            <a class="citerefentry" href="clCreateContextFromType.html"><span class="citerefentry"><span class="refentrytitle">clCreateContextFromType</span></span></a>,
            <a class="citerefentry" href="clRetainContext.html"><span class="citerefentry"><span class="refentrytitle">clRetainContext</span></span></a>,
            <a class="citerefentry" href="clReleaseContext.html"><span class="citerefentry"><span class="refentrytitle">clReleaseContext</span></span></a>,
            <a class="citerefentry" href="clGetContextInfo.html"><span class="citerefentry"><span class="refentrytitle">clGetContextInfo</span></span></a>,
            <a class="citerefentry" href="classDiagram.html"><span class="citerefentry"><span class="refentrytitle">Cardinality Diagram</span></span></a>
        </p>
      </div>
      <div xmlns="" class="refsect3" lang="en" xml:lang="en"><a xmlns="http://www.w3.org/1999/xhtml" id="Copyright"></a><h4 xmlns="http://www.w3.org/1999/xhtml"></h4><img xmlns="http://www.w3.org/1999/xhtml" src="KhronosLogo.jpg" /><p xmlns="http://www.w3.org/1999/xhtml"></p>Copyright © 2007-2011 The Khronos Group Inc. 
Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and/or associated documentation files (the
"Materials"), to deal in the Materials without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Materials, and to
permit persons to whom the Materials are furnished to do so, subject to
the condition that this copyright notice and permission notice shall be included
in all copies or substantial portions of the Materials. 
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