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 196   <div class="section" id="determine-if-a-keys-exists">
 197 <h1>Determine if a keys exists<a class="headerlink" href="#determine-if-a-keys-exists" title="Permalink to this headline">¶</a></h1>
 198 <div class="section" id="synopsis">
 199 <h2>SYNOPSIS<a class="headerlink" href="#synopsis" title="Permalink to this headline">¶</a></h2>
 200 <dl class="simple">
 201 <dt>#include &lt;libmemcached/memcached.h&gt;</dt><dd><p>Compile and link with -lmemcached</p>
 202 </dd>
 203 </dl>
 204 <dl class="cpp function">
 205 <dt id="_CPPv415memcached_existP12memcached_stPcP6size_t">
 206 <span id="_CPPv315memcached_existP12memcached_stPcP6size_t"></span><span id="_CPPv215memcached_existP12memcached_stPcP6size_t"></span><span id="memcached_exist__memcached_stP.cP.sP"></span><a class="reference internal" href="memcached_return_t.html#_CPPv418memcached_return_t" title="memcached_return_t">memcached_return_t</a> <code class="sig-name descname">memcached_exist</code><span class="sig-paren">(</span><a class="reference internal" href="memcached_create.html#_CPPv412memcached_st" title="memcached_st">memcached_st</a> *<em>ptr</em>, char *<em>key</em>, size_t *<em>key_length</em><span class="sig-paren">)</span><a class="headerlink" href="#_CPPv415memcached_existP12memcached_stPcP6size_t" title="Permalink to this definition">¶</a><br /></dt>
 207 <dd></dd></dl>
 208
 209 <dl class="cpp function">
 210 <dt id="_CPPv422memcached_exist_by_keyP12memcached_stPcP6size_tPcP6size_t">
 211 <span id="_CPPv322memcached_exist_by_keyP12memcached_stPcP6size_tPcP6size_t"></span><span id="_CPPv222memcached_exist_by_keyP12memcached_stPcP6size_tPcP6size_t"></span><span id="memcached_exist_by_key__memcached_stP.cP.sP.cP.sP"></span><a class="reference internal" href="memcached_return_t.html#_CPPv418memcached_return_t" title="memcached_return_t">memcached_return_t</a> <code class="sig-name descname">memcached_exist_by_key</code><span class="sig-paren">(</span><a class="reference internal" href="memcached_create.html#_CPPv412memcached_st" title="memcached_st">memcached_st</a> *<em>ptr</em>, char *<em>group_key</em>, size_t *<em>group_key_length</em>, char *<em>key</em>, size_t *<em>key_length</em><span class="sig-paren">)</span><a class="headerlink" href="#_CPPv422memcached_exist_by_keyP12memcached_stPcP6size_tPcP6size_t" title="Permalink to this definition">¶</a><br /></dt>
 212 <dd><dl class="field-list simple">
 213 <dt class="field-odd">Parameters</dt>
 214 <dd class="field-odd"><ul class="simple">
 215 <li><p><strong>ptr</strong> -- pointer to an initialized <a class="reference internal" href="memcached_create.html#_CPPv412memcached_st" title="memcached_st"><code class="xref cpp cpp-any docutils literal notranslate"><span class="pre">memcached_st</span></code></a> struct</p></li>
 216 <li><p><strong>group_key</strong> -- the key namespace</p></li>
 217 <li><p><strong>group_key_length</strong> -- length of the <a class="reference internal" href="#_CPPv422memcached_exist_by_keyP12memcached_stPcP6size_tPcP6size_t" title="memcached_exist_by_key::group_key"><code class="xref cpp cpp-any docutils literal notranslate"><span class="pre">group_key</span></code></a> without any terminating zero</p></li>
 218 <li><p><strong>key</strong> -- the key to check</p></li>
 219 <li><p><strong>key_length</strong> -- length of the <a class="reference internal" href="#_CPPv422memcached_exist_by_keyP12memcached_stPcP6size_tPcP6size_t" title="memcached_exist_by_key::key"><code class="xref cpp cpp-any docutils literal notranslate"><span class="pre">key</span></code></a> without any terminating zero</p></li>
 220 </ul>
 221 </dd>
 222 <dt class="field-even">Returns</dt>
 223 <dd class="field-even"><p><a class="reference internal" href="memcached_return_t.html#_CPPv418memcached_return_t" title="memcached_return_t"><code class="xref cpp cpp-any docutils literal notranslate"><span class="pre">memcached_return_t</span></code></a> indicating success</p>
 224 </dd>
 225 </dl>
 226 </dd></dl>
 227
 228 <div class="versionadded">
 229 <p><span class="versionmodified added">New in version 0.53.</span></p>
 230 </div>
 231 </div>
 232 <div class="section" id="description">
 233 <h2>DESCRIPTION<a class="headerlink" href="#description" title="Permalink to this headline">¶</a></h2>
 234 <p><a class="reference internal" href="#_CPPv415memcached_existP12memcached_stPcP6size_t" title="memcached_exist"><code class="xref cpp cpp-func docutils literal notranslate"><span class="pre">memcached_exist()</span></code></a> can be used to check if a key exists.</p>
 235 </div>
 236 <div class="section" id="return-value">
 237 <h2>RETURN VALUE<a class="headerlink" href="#return-value" title="Permalink to this headline">¶</a></h2>
 238 <dl class="simple">
 239 <dt><a class="reference internal" href="memcached_return_t.html#_CPPv4N18memcached_return_t17MEMCACHED_SUCCESSE" title="MEMCACHED_SUCCESS"><code class="xref cpp cpp-any docutils literal notranslate"><span class="pre">MEMCACHED_SUCCESS</span></code></a></dt><dd><p>The key exists.</p>
 240 </dd>
 241 <dt><a class="reference internal" href="memcached_return_t.html#_CPPv4N18memcached_return_t18MEMCACHED_NOTFOUNDE" title="MEMCACHED_NOTFOUND"><code class="xref cpp cpp-any docutils literal notranslate"><span class="pre">MEMCACHED_NOTFOUND</span></code></a></dt><dd><p>The key was not found.</p>
 242 </dd>
 243 </dl>
 244 </div>
 245 <div class="section" id="see-also">
 246 <h2>SEE ALSO<a class="headerlink" href="#see-also" title="Permalink to this headline">¶</a></h2>
 247 <ul class="simple">
 248 <li><p><em class="manpage"><a class="manpage reference external" href="https://linux.die.net/man/1/memcached">memcached(1)</a></em></p></li>
 249 <li><p><a class="reference internal" href="../libmemcached.html"><span class="doc">C/C++ Client Library for memcached</span></a></p></li>
 250 <li><p><a class="reference internal" href="memcached_strerror.html"><span class="doc">Converting Error Codes to Messages</span></a></p></li>
 251 </ul>
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