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 213   <div class="section" id="use-custom-allocators-for-embedded-usage">
 214 <h1>Use custom allocators for embedded usage<a class="headerlink" href="#use-custom-allocators-for-embedded-usage" title="Permalink to this headline">¶</a></h1>
 215 <p>Manage memory allocator functions</p>
 216 <div class="section" id="synopsis">
 217 <h2>SYNOPSIS<a class="headerlink" href="#synopsis" title="Permalink to this headline">¶</a></h2>
 218 <dl class="simple">
 219 <dt>#include &lt;libmemcached/memcached.h&gt;</dt><dd><p>Compile and link with -lmemcached</p>
 220 </dd>
 221 </dl>
 222 <dl class="function">
 223 <dt id="_CPPv431memcached_set_memory_allocatorsP12memcached_st19memcached_malloc_fn17memcached_free_fn20memcached_realloc_fn19memcached_calloc_fnPv">
 224 <span id="_CPPv331memcached_set_memory_allocatorsP12memcached_st19memcached_malloc_fn17memcached_free_fn20memcached_realloc_fn19memcached_calloc_fnPv"></span><span id="_CPPv231memcached_set_memory_allocatorsP12memcached_st19memcached_malloc_fn17memcached_free_fn20memcached_realloc_fn19memcached_calloc_fnPv"></span><span id="memcached_set_memory_allocators__memcached_stP.memcached_malloc_fn.memcached_free_fn.memcached_realloc_fn.memcached_calloc_fn.voidP"></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_set_memory_allocators</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>, <a class="reference internal" href="#_CPPv419memcached_malloc_fn" title="memcached_malloc_fn">memcached_malloc_fn</a> <em>mem_malloc</em>, <a class="reference internal" href="#_CPPv417memcached_free_fn" title="memcached_free_fn">memcached_free_fn</a> <em>mem_free</em>, <a class="reference internal" href="#_CPPv420memcached_realloc_fn" title="memcached_realloc_fn">memcached_realloc_fn</a> <em>mem_realloc</em>, <a class="reference internal" href="#_CPPv419memcached_calloc_fn" title="memcached_calloc_fn">memcached_calloc_fn</a> <em>mem_calloc</em>, void *<em>context</em><span class="sig-paren">)</span><a class="headerlink" href="#_CPPv431memcached_set_memory_allocatorsP12memcached_st19memcached_malloc_fn17memcached_free_fn20memcached_realloc_fn19memcached_calloc_fnPv" title="Permalink to this definition">¶</a><br /></dt>
 225 <dd></dd></dl>
 226
 227 <dl class="function">
 228 <dt id="_CPPv431memcached_get_memory_allocatorsP12memcached_stP19memcached_malloc_fnP17memcached_free_fnP20memcached_realloc_fnP19memcached_calloc_fn">
 229 <span id="_CPPv331memcached_get_memory_allocatorsP12memcached_stP19memcached_malloc_fnP17memcached_free_fnP20memcached_realloc_fnP19memcached_calloc_fn"></span><span id="_CPPv231memcached_get_memory_allocatorsP12memcached_stP19memcached_malloc_fnP17memcached_free_fnP20memcached_realloc_fnP19memcached_calloc_fn"></span><span id="memcached_get_memory_allocators__memcached_stP.memcached_malloc_fnP.memcached_free_fnP.memcached_realloc_fnP.memcached_calloc_fnP"></span>void <code class="sig-name descname">memcached_get_memory_allocators</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>, <a class="reference internal" href="#_CPPv419memcached_malloc_fn" title="memcached_malloc_fn">memcached_malloc_fn</a> *<em>mem_malloc</em>, <a class="reference internal" href="#_CPPv417memcached_free_fn" title="memcached_free_fn">memcached_free_fn</a> *<em>mem_free</em>, <a class="reference internal" href="#_CPPv420memcached_realloc_fn" title="memcached_realloc_fn">memcached_realloc_fn</a> *<em>mem_realloc</em>, <a class="reference internal" href="#_CPPv419memcached_calloc_fn" title="memcached_calloc_fn">memcached_calloc_fn</a> *<em>mem_calloc</em><span class="sig-paren">)</span><a class="headerlink" href="#_CPPv431memcached_get_memory_allocatorsP12memcached_stP19memcached_malloc_fnP17memcached_free_fnP20memcached_realloc_fnP19memcached_calloc_fn" title="Permalink to this definition">¶</a><br /></dt>
 230 <dd></dd></dl>
 231
 232 <dl class="function">
 233 <dt id="_CPPv439memcached_get_memory_allocators_contextPK12memcached_st">
 234 <span id="_CPPv339memcached_get_memory_allocators_contextPK12memcached_st"></span><span id="_CPPv239memcached_get_memory_allocators_contextPK12memcached_st"></span><span id="memcached_get_memory_allocators_context__memcached_stCP"></span>void *<code class="sig-name descname">memcached_get_memory_allocators_context</code><span class="sig-paren">(</span><em class="property">const</em> <a class="reference internal" href="memcached_create.html#_CPPv412memcached_st" title="memcached_st">memcached_st</a> *<em>ptr</em><span class="sig-paren">)</span><a class="headerlink" href="#_CPPv439memcached_get_memory_allocators_contextPK12memcached_st" title="Permalink to this definition">¶</a><br /></dt>
 235 <dd></dd></dl>
 236
 237 <dl class="type">
 238 <dt id="_CPPv419memcached_malloc_fn">
 239 <span id="_CPPv319memcached_malloc_fn"></span><span id="_CPPv219memcached_malloc_fn"></span><span id="memcached_malloc_fn"></span><em class="property">typedef </em>void *(*<code class="sig-name descname">memcached_malloc_fn</code>)<span class="sig-paren">(</span><a class="reference internal" href="memcached_create.html#_CPPv412memcached_st" title="memcached_st">memcached_st</a> *ptr, <em class="property">const</em> size_t size, void *context<span class="sig-paren">)</span><a class="headerlink" href="#_CPPv419memcached_malloc_fn" title="Permalink to this definition">¶</a><br /></dt>
 240 <dd></dd></dl>
 241
 242 <dl class="type">
 243 <dt id="_CPPv420memcached_realloc_fn">
 244 <span id="_CPPv320memcached_realloc_fn"></span><span id="_CPPv220memcached_realloc_fn"></span><span id="memcached_realloc_fn"></span><em class="property">typedef </em>void *(*<code class="sig-name descname">memcached_realloc_fn</code>)<span class="sig-paren">(</span><a class="reference internal" href="memcached_create.html#_CPPv412memcached_st" title="memcached_st">memcached_st</a> *ptr, void *mem, <em class="property">const</em> size_t size, void *context<span class="sig-paren">)</span><a class="headerlink" href="#_CPPv420memcached_realloc_fn" title="Permalink to this definition">¶</a><br /></dt>
 245 <dd></dd></dl>
 246
 247 <dl class="type">
 248 <dt id="_CPPv417memcached_free_fn">
 249 <span id="_CPPv317memcached_free_fn"></span><span id="_CPPv217memcached_free_fn"></span><span id="memcached_free_fn"></span><em class="property">typedef </em>void (*<code class="sig-name descname">memcached_free_fn</code>)<span class="sig-paren">(</span><a class="reference internal" href="memcached_create.html#_CPPv412memcached_st" title="memcached_st">memcached_st</a> *ptr, void *mem, void *context<span class="sig-paren">)</span><a class="headerlink" href="#_CPPv417memcached_free_fn" title="Permalink to this definition">¶</a><br /></dt>
 250 <dd></dd></dl>
 251
 252 <dl class="type">
 253 <dt id="_CPPv419memcached_calloc_fn">
 254 <span id="_CPPv319memcached_calloc_fn"></span><span id="_CPPv219memcached_calloc_fn"></span><span id="memcached_calloc_fn"></span><em class="property">typedef </em>void *(*<code class="sig-name descname">memcached_calloc_fn</code>)<span class="sig-paren">(</span><a class="reference internal" href="memcached_create.html#_CPPv412memcached_st" title="memcached_st">memcached_st</a> *ptr, size_t nelem, <em class="property">const</em> size_t elsize, void *context<span class="sig-paren">)</span><a class="headerlink" href="#_CPPv419memcached_calloc_fn" title="Permalink to this definition">¶</a><br /></dt>
 255 <dd></dd></dl>
 256
 257 </div>
 258 <div class="section" id="description">
 259 <h2>DESCRIPTION<a class="headerlink" href="#description" title="Permalink to this headline">¶</a></h2>
 260 <p><code class="xref cpp cpp-any docutils literal notranslate"><span class="pre">libmemcached</span></code> allows you to specify your own memory allocators, optimized for
 261 your application. This enables libmemcached to be used inside of applications
 262 that have their own malloc implementation.</p>
 263 <p><a class="reference internal" href="#_CPPv431memcached_set_memory_allocatorsP12memcached_st19memcached_malloc_fn17memcached_free_fn20memcached_realloc_fn19memcached_calloc_fnPv" title="memcached_set_memory_allocators"><code class="xref cpp cpp-func docutils literal notranslate"><span class="pre">memcached_set_memory_allocators()</span></code></a> is used to set the memory allocators
 264 used by the memcached instance specified by ptr. Please note that you cannot
 265 override only one of the memory allocators, you have to specify a complete new
 266 set if you want to override one of them. All of the memory allocation functions
 267 should behave as specified in the C99 standard. Specify NULL as all functions to
 268 reset them to the default values.</p>
 269 <p><a class="reference internal" href="#_CPPv431memcached_get_memory_allocatorsP12memcached_stP19memcached_malloc_fnP17memcached_free_fnP20memcached_realloc_fnP19memcached_calloc_fn" title="memcached_get_memory_allocators"><code class="xref cpp cpp-func docutils literal notranslate"><span class="pre">memcached_get_memory_allocators()</span></code></a> is used to get the currently used memory
 270 allocators by a memcached handle.</p>
 271 <p><a class="reference internal" href="#_CPPv439memcached_get_memory_allocators_contextPK12memcached_st" title="memcached_get_memory_allocators_context"><code class="xref cpp cpp-func docutils literal notranslate"><span class="pre">memcached_get_memory_allocators_context()</span></code></a> returns the void * that was
 272 passed in during the call to <a class="reference internal" href="#_CPPv431memcached_set_memory_allocatorsP12memcached_st19memcached_malloc_fn17memcached_free_fn20memcached_realloc_fn19memcached_calloc_fnPv" title="memcached_set_memory_allocators"><code class="xref cpp cpp-func docutils literal notranslate"><span class="pre">memcached_set_memory_allocators()</span></code></a>.</p>
 273 <p>The first argument to the memory allocator functions is a pointer to a memcached
 274 structure, the is passed as const and you will need to clone it in order to make
 275 use of any operation which would modify it.</p>
 276 </div>
 277 <div class="section" id="notes">
 278 <h2>NOTES<a class="headerlink" href="#notes" title="Permalink to this headline">¶</a></h2>
 279 <p>In version 0.38 all functions were modified to have a context void pointer
 280 passed to them. This was so that customer allocators could have their own space
 281 for memory.</p>
 282 </div>
 283 <div class="section" id="return">
 284 <h2>RETURN<a class="headerlink" href="#return" title="Permalink to this headline">¶</a></h2>
 285 <p><a class="reference internal" href="#_CPPv431memcached_set_memory_allocatorsP12memcached_st19memcached_malloc_fn17memcached_free_fn20memcached_realloc_fn19memcached_calloc_fnPv" title="memcached_set_memory_allocators"><code class="xref cpp cpp-func docutils literal notranslate"><span class="pre">memcached_set_memory_allocators()</span></code></a> return <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> upon success,
 286 and <a class="reference internal" href="memcached_return_t.html#_CPPv4N18memcached_return_t17MEMCACHED_FAILUREE" title="MEMCACHED_FAILURE"><code class="xref cpp cpp-any docutils literal notranslate"><span class="pre">MEMCACHED_FAILURE</span></code></a> if you don’t pass a complete set of function pointers.</p>
 287 </div>
 288 <div class="section" id="see-also">
 289 <h2>SEE ALSO<a class="headerlink" href="#see-also" title="Permalink to this headline">¶</a></h2>
 290 <ul class="simple">
 291 <li><p><em class="manpage"><a class="manpage reference external" href="http://man7.org/linux/man-pages/man1/memcached.1.html">memcached(1)</a></em></p></li>
 292 <li><p><a class="reference internal" href="../libmemcached.html"><span class="doc">C/C++ Client Library for memcached</span></a></p></li>
 293 <li><p><a class="reference internal" href="memcached_strerror.html"><span class="doc">Converting Error Codes to Messages</span></a></p></li>
 294 </ul>
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