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    <title>clGetPlatformIDs</title>
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    <div class="refentry">
      <a id="id-1"></a>
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      <div xmlns="" class="refnamediv">
        <a xmlns="http://www.w3.org/1999/xhtml" id="clGetPlatformIDs"></a>
        <h1>clGetPlatformIDs</h1>
        <p>Obtain the list of platforms available.</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="scalarDataTypes.html" target="pagedisplay">cl_int</a> <strong class="fsfunc">clGetPlatformIDs</strong>(</code>
                <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_entries</var>, </td>
              </td>
            </tr>
            <tr valign="top">
              <td> </td>
              <td><a xmlns="http://www.w3.org/1999/xhtml" class="link" href="abstractDataTypes.html" target="pagedisplay">cl_platform_id</a> <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">*platforms</var>, </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_platforms</var><code>)</code></td>
            </tr>
          </table>
        </div>
      </div>
      <div class="refsect1">
        <a id="parameters"></a>
        <h2>Parameters</h2>
        <div class="variablelist">
          <dl class="variablelist">
            <dt>
              <span class="term">
                <code class="varname">num_entries</code>
              </span>
            </dt>
            <dd>
              <p>
                  The number of <a class="link" href="abstractDataTypes.html" target="pagedisplay">cl_platform_id</a>
                  entries that can be added to <code class="varname">platforms</code>. If
                  <code class="varname">platforms</code> is not NULL, the <code class="varname">num_entries</code>
                  must be greater than zero.
                </p>
            </dd>
            <dt>
              <span class="term">
                <code class="varname">platforms</code>
              </span>
            </dt>
            <dd>
              <p>
                  Returns a list of OpenCL platforms found. The <a class="link" href="abstractDataTypes.html" target="pagedisplay">cl_platform_id</a> values returned
                  in <code class="varname">platforms</code> can be used to identify a specific OpenCL
                  platform. If <code class="varname">platforms</code> argument is NULL, this argument
                  is ignored. The number of OpenCL platforms returned is the mininum of the
                  value specified by <code class="varname">num_entries</code> or the number of OpenCL
                  platforms available.
                </p>
            </dd>
            <dt>
              <span class="term">
                <code class="varname">num_platforms</code>
              </span>
            </dt>
            <dd>
              <p>
                  Returns the number of OpenCL platforms available. If
                  <code class="varname">num_platforms</code> is NULL, this argument is ignored.
                </p>
            </dd>
          </dl>
        </div>
      </div>
      <div class="refsect1">
        <a id="errors"></a>
        <h2>Errors</h2>
        <p>
            Returns <span class="errorname">CL_SUCCESS</span> if the function is executed
            successfully. If the 
            <a class="citerefentry" href="cl_khr_icd.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_icd</span></span></a>
            extension is enabled, <code class="function">clGetPlatformIDs</code> returns 
            <span class="errorname">CL_SUCCESS</span> if the function is executed successfully 
            and there are a non zero number of platforms available.
        </p>
        <p>
          Otherwise it returns one of the following errors:
        </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_VALUE</span> if <code class="varname">num_entries</code> 
                is equal to zero and <code class="varname">platforms</code> is not NULL or if 
                both <code class="varname">num_platforms</code> and 
                <code class="varname">platforms</code> are NULL.
            </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_PLATFORM_NOT_FOUND_KHR</span> if the 
                <a class="citerefentry" href="cl_khr_icd.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_icd</span></span></a>
                extension is enabled and no platforms are found.
            </li>
          </ul>
        </div>
      </div>
      <div class="refsect1">
        <a id="specification"></a>
        <h2>Specification</h2>
        <p><img src="pdficon_small1.gif" />
            <a href="https://www.khronos.org/registry/cl/specs/opencl-2.1.pdf#page=62" target="OpenCL Spec">OpenCL Specification</a>
        </p>
      </div>
      <div class="refsect1">
        <a id="seealso"></a>
        <h2>Also see</h2>
        <p>
           <a class="citerefentry" href="clGetPlatformInfo.html"><span class="citerefentry"><span class="refentrytitle">clGetPlatformInfo</span></span></a>,
           <a class="citerefentry" href="clGetDeviceInfo.html"><span class="citerefentry"><span class="refentrytitle">clGetDeviceInfo</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 © 2007-2015 The Khronos Group Inc.
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"Materials"), to deal in the Materials without restriction, including
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