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129 <li class=
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</a></li>
130 <li class=
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</a></li>
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</a></li>
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</a></li>
133 <li class=
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</a></li>
134 <li class=
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"reference internal" href=
"../bin/memflush.html">memflush - flush all data from a server
</a></li>
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</a></li>
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</a></li>
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212 <h1>Retrieving data from the server
<a class=
"headerlink" href=
"#retrieving-data-from-the-server" title=
"Permalink to this headline">¶
</a></h1>
213 <div class=
"section" id=
"synopsis">
214 <span id=
"index-0"></span><h2>SYNOPSIS
<a class=
"headerlink" href=
"#synopsis" title=
"Permalink to this headline">¶
</a></h2>
215 <p>#include
<libmemcached/memcached.h
></p>
216 <dl class=
"function">
217 <dt id=
"_CPPv422memcached_fetch_resultP12memcached_stP19memcached_result_stP18memcached_return_t">
218 <span id=
"_CPPv322memcached_fetch_resultP12memcached_stP19memcached_result_stP18memcached_return_t"></span><span id=
"_CPPv222memcached_fetch_resultP12memcached_stP19memcached_result_stP18memcached_return_t"></span><span id=
"memcached_fetch_result__memcached_stP.memcached_result_stP.memcached_return_tP"></span><a class=
"reference internal" href=
"memcached_result_st.html#_CPPv419memcached_result_st" title=
"memcached_result_st">memcached_result_st
</a> *
<code class=
"sig-name descname">memcached_fetch_result
</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=
"memcached_result_st.html#_CPPv419memcached_result_st" title=
"memcached_result_st">memcached_result_st
</a> *
<em>result
</em>,
<a class=
"reference internal" href=
"memcached_return_t.html#_CPPv418memcached_return_t" title=
"memcached_return_t">memcached_return_t
</a> *
<em>error
</em><span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv422memcached_fetch_resultP12memcached_stP19memcached_result_stP18memcached_return_t" title=
"Permalink to this definition">¶
</a><br /></dt>
221 <dl class=
"function">
222 <dt id=
"_CPPv413memcached_getP12memcached_stPKc6size_tP6size_tP8uint32_tP18memcached_return_t">
223 <span id=
"_CPPv313memcached_getP12memcached_stPKc6size_tP6size_tP8uint32_tP18memcached_return_t"></span><span id=
"_CPPv213memcached_getP12memcached_stPKc6size_tP6size_tP8uint32_tP18memcached_return_t"></span><span id=
"memcached_get__memcached_stP.cCP.s.sP.uint32_tP.memcached_return_tP"></span>char *
<code class=
"sig-name descname">memcached_get
</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>,
<em class=
"property">const
</em> char *
<em>key
</em>, size_t
<em>key_length
</em>, size_t *
<em>value_length
</em>, uint32_t *
<em>flags
</em>,
<a class=
"reference internal" href=
"memcached_return_t.html#_CPPv418memcached_return_t" title=
"memcached_return_t">memcached_return_t
</a> *
<em>error
</em><span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv413memcached_getP12memcached_stPKc6size_tP6size_tP8uint32_tP18memcached_return_t" title=
"Permalink to this definition">¶
</a><br /></dt>
226 <dl class=
"function">
227 <dt id=
"_CPPv414memcached_mgetP12memcached_stPPCKcPK6size_t6size_t">
228 <span id=
"_CPPv314memcached_mgetP12memcached_stPPCKcPK6size_t6size_t"></span><span id=
"_CPPv214memcached_mgetP12memcached_stPPCKcPK6size_t6size_t"></span><span id=
"memcached_mget__memcached_stP.cCPCP.sCP.s"></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_mget
</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>,
<em class=
"property">const
</em> char *
<em class=
"property">const
</em> *
<em>keys
</em>,
<em class=
"property">const
</em> size_t *
<em>key_length
</em>, size_t
<em>number_of_keys
</em><span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv414memcached_mgetP12memcached_stPPCKcPK6size_t6size_t" title=
"Permalink to this definition">¶
</a><br /></dt>
231 <dl class=
"function">
232 <dt id=
"_CPPv420memcached_get_by_keyP12memcached_stPKc6size_tPKc6size_tP6size_tP8uint32_tP18memcached_return_t">
233 <span id=
"_CPPv320memcached_get_by_keyP12memcached_stPKc6size_tPKc6size_tP6size_tP8uint32_tP18memcached_return_t"></span><span id=
"_CPPv220memcached_get_by_keyP12memcached_stPKc6size_tPKc6size_tP6size_tP8uint32_tP18memcached_return_t"></span><span id=
"memcached_get_by_key__memcached_stP.cCP.s.cCP.s.sP.uint32_tP.memcached_return_tP"></span>char *
<code class=
"sig-name descname">memcached_get_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>,
<em class=
"property">const
</em> char *
<em>group_key
</em>, size_t
<em>group_key_length
</em>,
<em class=
"property">const
</em> char *
<em>key
</em>, size_t
<em>key_length
</em>, size_t *
<em>value_length
</em>, uint32_t *
<em>flags
</em>,
<a class=
"reference internal" href=
"memcached_return_t.html#_CPPv418memcached_return_t" title=
"memcached_return_t">memcached_return_t
</a> *
<em>error
</em><span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv420memcached_get_by_keyP12memcached_stPKc6size_tPKc6size_tP6size_tP8uint32_tP18memcached_return_t" title=
"Permalink to this definition">¶
</a><br /></dt>
236 <dl class=
"function">
237 <dt id=
"_CPPv421memcached_mget_by_keyP12memcached_stPKc6size_tPPCKcPK6size_t6size_t">
238 <span id=
"_CPPv321memcached_mget_by_keyP12memcached_stPKc6size_tPPCKcPK6size_t6size_t"></span><span id=
"_CPPv221memcached_mget_by_keyP12memcached_stPKc6size_tPPCKcPK6size_t6size_t"></span><span id=
"memcached_mget_by_key__memcached_stP.cCP.s.cCPCP.sCP.s"></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_mget_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>,
<em class=
"property">const
</em> char *
<em>group_key
</em>, size_t
<em>group_key_length
</em>,
<em class=
"property">const
</em> char *
<em class=
"property">const
</em> *
<em>keys
</em>,
<em class=
"property">const
</em> size_t *
<em>key_length
</em>, size_t
<em>number_of_keys
</em><span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv421memcached_mget_by_keyP12memcached_stPKc6size_tPPCKcPK6size_t6size_t" title=
"Permalink to this definition">¶
</a><br /></dt>
241 <dl class=
"function">
242 <dt id=
"_CPPv423memcached_fetch_executeP12memcached_stP20memcached_execute_fnPv8uint32_t">
243 <span id=
"_CPPv323memcached_fetch_executeP12memcached_stP20memcached_execute_fnPv8uint32_t"></span><span id=
"_CPPv223memcached_fetch_executeP12memcached_stP20memcached_execute_fnPv8uint32_t"></span><span id=
"memcached_fetch_execute__memcached_stP.memcached_execute_fnP.voidP.uint32_t"></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_fetch_execute
</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=
"#_CPPv420memcached_execute_fn" title=
"memcached_execute_fn">memcached_execute_fn
</a> *
<em>callback
</em>, void *
<em>context
</em>, uint32_t
<em>number_of_callbacks
</em><span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv423memcached_fetch_executeP12memcached_stP20memcached_execute_fnPv8uint32_t" title=
"Permalink to this definition">¶
</a><br /></dt>
246 <dl class=
"function">
247 <dt id=
"_CPPv422memcached_mget_executeP12memcached_stPPCKcPK6size_t6size_tP20memcached_execute_fnPv8uint32_t">
248 <span id=
"_CPPv322memcached_mget_executeP12memcached_stPPCKcPK6size_t6size_tP20memcached_execute_fnPv8uint32_t"></span><span id=
"_CPPv222memcached_mget_executeP12memcached_stPPCKcPK6size_t6size_tP20memcached_execute_fnPv8uint32_t"></span><span id=
"memcached_mget_execute__memcached_stP.cCPCP.sCP.s.memcached_execute_fnP.voidP.uint32_t"></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_mget_execute
</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>,
<em class=
"property">const
</em> char *
<em class=
"property">const
</em> *
<em>keys
</em>,
<em class=
"property">const
</em> size_t *
<em>key_length
</em>, size_t
<em>number_of_keys
</em>,
<a class=
"reference internal" href=
"#_CPPv420memcached_execute_fn" title=
"memcached_execute_fn">memcached_execute_fn
</a> *
<em>callback
</em>, void *
<em>context
</em>, uint32_t
<em>number_of_callbacks
</em><span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv422memcached_mget_executeP12memcached_stPPCKcPK6size_t6size_tP20memcached_execute_fnPv8uint32_t" title=
"Permalink to this definition">¶
</a><br /></dt>
251 <dl class=
"function">
252 <dt id=
"_CPPv429memcached_mget_execute_by_keyP12memcached_stPKc6size_tPPCKcPK6size_t6size_tP20memcached_execute_fnPv8uint32_t">
253 <span id=
"_CPPv329memcached_mget_execute_by_keyP12memcached_stPKc6size_tPPCKcPK6size_t6size_tP20memcached_execute_fnPv8uint32_t"></span><span id=
"_CPPv229memcached_mget_execute_by_keyP12memcached_stPKc6size_tPPCKcPK6size_t6size_tP20memcached_execute_fnPv8uint32_t"></span><span id=
"memcached_mget_execute_by_key__memcached_stP.cCP.s.cCPCP.sCP.s.memcached_execute_fnP.voidP.uint32_t"></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_mget_execute_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>,
<em class=
"property">const
</em> char *
<em>group_key
</em>, size_t
<em>group_key_length
</em>,
<em class=
"property">const
</em> char *
<em class=
"property">const
</em> *
<em>keys
</em>,
<em class=
"property">const
</em> size_t *
<em>key_length
</em>, size_t
<em>number_of_keys
</em>,
<a class=
"reference internal" href=
"#_CPPv420memcached_execute_fn" title=
"memcached_execute_fn">memcached_execute_fn
</a> *
<em>callback
</em>, void *
<em>context
</em>, uint32_t
<em>number_of_callbacks
</em><span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv429memcached_mget_execute_by_keyP12memcached_stPKc6size_tPPCKcPK6size_t6size_tP20memcached_execute_fnPv8uint32_t" title=
"Permalink to this definition">¶
</a><br /></dt>
257 <dt id=
"_CPPv420memcached_execute_fn">
258 <span id=
"_CPPv320memcached_execute_fn"></span><span id=
"_CPPv220memcached_execute_fn"></span><span id=
"memcached_execute_fn"></span><em class=
"property">typedef
</em><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_execute_fn
</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> *ptr,
<a class=
"reference internal" href=
"memcached_result_st.html#_CPPv419memcached_result_st" title=
"memcached_result_st">memcached_result_st
</a> *result, void *context
<span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv420memcached_execute_fn" title=
"Permalink to this definition">¶
</a><br /></dt>
261 <p>Compile and link with -lmemcached
</p>
263 <div class=
"section" id=
"description">
264 <h2>DESCRIPTION
<a class=
"headerlink" href=
"#description" title=
"Permalink to this headline">¶
</a></h2>
265 <p><a class=
"reference internal" href=
"#_CPPv413memcached_getP12memcached_stPKc6size_tP6size_tP8uint32_tP18memcached_return_t" title=
"memcached_get"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_get()
</span></code></a> is used to fetch an individual value from the server.
266 You must pass in a key and its length to fetch the object. You must supply
267 three pointer variables which will give you the state of the returned
268 object. A
<code class=
"xref cpp cpp-type docutils literal notranslate"><span class=
"pre">uint32_t
</span></code> pointer to contain whatever flags you stored with the value, a
<code class=
"xref cpp cpp-type docutils literal notranslate"><span class=
"pre">size_t
</span></code> pointer which will be filled with size of of
269 the object, and a
<a class=
"reference internal" href=
"memcached_return_t.html#_CPPv418memcached_return_t" title=
"memcached_return_t"><code class=
"xref cpp cpp-type docutils literal notranslate"><span class=
"pre">memcached_return_t
</span></code></a> pointer to hold any error. The
270 object will be returned upon success and NULL will be returned on failure. Any
271 object returned by
<a class=
"reference internal" href=
"#_CPPv413memcached_getP12memcached_stPKc6size_tP6size_tP8uint32_tP18memcached_return_t" title=
"memcached_get"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_get()
</span></code></a> must be released by the caller
273 <p><a class=
"reference internal" href=
"#_CPPv414memcached_mgetP12memcached_stPPCKcPK6size_t6size_t" title=
"memcached_mget"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_mget()
</span></code></a> is used to select multiple keys at once. For
274 multiple key operations it is always faster to use this function. This function always works asynchronously.
</p>
275 <p>To retrieve data after a successful execution of
<a class=
"reference internal" href=
"#_CPPv414memcached_mgetP12memcached_stPPCKcPK6size_t6size_t" title=
"memcached_mget"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_mget()
</span></code></a>, you will need to
276 call
<a class=
"reference internal" href=
"#_CPPv422memcached_fetch_resultP12memcached_stP19memcached_result_stP18memcached_return_t" title=
"memcached_fetch_result"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_fetch_result()
</span></code></a>. You should continue to call this function until
277 it returns a NULL (i.e. no more values). If you need to quit in the middle of a
278 <a class=
"reference internal" href=
"#_CPPv414memcached_mgetP12memcached_stPPCKcPK6size_t6size_t" title=
"memcached_mget"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_mget()
</span></code></a> call, you can execute a
<a class=
"reference internal" href=
"memcached_quit.html#_CPPv414memcached_quitP12memcached_st" title=
"memcached_quit"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_quit()
</span></code></a>, those this is not required.
</p>
279 <p><a class=
"reference internal" href=
"#_CPPv422memcached_fetch_resultP12memcached_stP19memcached_result_stP18memcached_return_t" title=
"memcached_fetch_result"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_fetch_result()
</span></code></a> is used to fetch an individual value from the server.
<a class=
"reference internal" href=
"#_CPPv414memcached_mgetP12memcached_stPPCKcPK6size_t6size_t" title=
"memcached_mget"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_mget()
</span></code></a> must always be called before using this method.
280 You must pass in a key and its length to fetch the object. You must supply
281 three pointer variables which will give you the state of the returned
282 object. A
<code class=
"xref cpp cpp-type docutils literal notranslate"><span class=
"pre">uint32_t
</span></code> pointer to contain whatever flags you stored with the value, a
<code class=
"xref cpp cpp-type docutils literal notranslate"><span class=
"pre">size_t
</span></code> pointer which will be filled with size of of the
283 object, and a
<a class=
"reference internal" href=
"memcached_return_t.html#_CPPv418memcached_return_t" title=
"memcached_return_t"><code class=
"xref cpp cpp-type docutils literal notranslate"><span class=
"pre">memcached_return_t
</span></code></a> pointer to hold any error. The
284 object will be returned upon success and NULL will be returned on failure.
<a class=
"reference internal" href=
"memcached_return_t.html#_CPPv4N18memcached_return_t13MEMCACHED_ENDE" title=
"MEMCACHED_END"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">MEMCACHED_END
</span></code></a> is returned by the *error value when all objects that have been found are returned. The final value upon
<a class=
"reference internal" href=
"memcached_return_t.html#_CPPv4N18memcached_return_t13MEMCACHED_ENDE" title=
"MEMCACHED_END"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">MEMCACHED_END
</span></code></a> is null.
</p>
285 <p><a class=
"reference internal" href=
"#_CPPv422memcached_fetch_resultP12memcached_stP19memcached_result_stP18memcached_return_t" title=
"memcached_fetch_result"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_fetch_result()
</span></code></a> is used to return a
<a class=
"reference internal" href=
"memcached_result_st.html#_CPPv419memcached_result_st" title=
"memcached_result_st"><code class=
"xref cpp cpp-type docutils literal notranslate"><span class=
"pre">memcached_result_st
</span></code></a> structure from a memcached server. The result object is forward compatible
286 with changes to the server. For more information please refer to the
287 <a class=
"reference internal" href=
"memcached_result_st.html#_CPPv419memcached_result_st" title=
"memcached_result_st"><code class=
"xref cpp cpp-type docutils literal notranslate"><span class=
"pre">memcached_result_st
</span></code></a> help. This function will dynamically allocate a
288 result structure for you if you do not pass one to the function.
</p>
289 <p><a class=
"reference internal" href=
"#_CPPv423memcached_fetch_executeP12memcached_stP20memcached_execute_fnPv8uint32_t" title=
"memcached_fetch_execute"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_fetch_execute()
</span></code></a> is a callback function for result sets.
290 Instead of returning the results to you for processing, it passes each of the
291 result sets to the list of functions you provide. It passes to the function
292 a
<a class=
"reference internal" href=
"memcached_create.html#_CPPv412memcached_st" title=
"memcached_st"><code class=
"xref cpp cpp-type docutils literal notranslate"><span class=
"pre">memcached_st
</span></code></a> that can be cloned for use in the called
293 function (it can not be used directly). It also passes a result set which does
294 not need to be freed. Finally it passes a “context”. This is just a pointer to
295 a memory reference you supply the calling function. Currently only one value
296 is being passed to each function call. In the future there will be an option
297 to allow this to be an array.
</p>
298 <p><a class=
"reference internal" href=
"#_CPPv422memcached_mget_executeP12memcached_stPPCKcPK6size_t6size_tP20memcached_execute_fnPv8uint32_t" title=
"memcached_mget_execute"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_mget_execute()
</span></code></a> and
<a class=
"reference internal" href=
"#_CPPv429memcached_mget_execute_by_keyP12memcached_stPKc6size_tPPCKcPK6size_t6size_tP20memcached_execute_fnPv8uint32_t" title=
"memcached_mget_execute_by_key"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_mget_execute_by_key()
</span></code></a>
299 is similar to
<a class=
"reference internal" href=
"#_CPPv414memcached_mgetP12memcached_stPPCKcPK6size_t6size_t" title=
"memcached_mget"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_mget()
</span></code></a>, but it may trigger the supplied
300 callbacks with result sets while sending out the queries. If you try to
301 perform a really large multiget with
<a class=
"reference internal" href=
"#_CPPv414memcached_mgetP12memcached_stPPCKcPK6size_t6size_t" title=
"memcached_mget"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_mget()
</span></code></a> you may
302 encounter a deadlock in the OS kernel (it will fail to write data to the
303 socket because the input buffer is full).
<a class=
"reference internal" href=
"#_CPPv422memcached_mget_executeP12memcached_stPPCKcPK6size_t6size_tP20memcached_execute_fnPv8uint32_t" title=
"memcached_mget_execute"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_mget_execute()
</span></code></a>
304 solves this problem by processing some of the results before continuing
305 sending out requests. Please note that this function is only available in
306 the binary protocol.
</p>
307 <p><a class=
"reference internal" href=
"#_CPPv420memcached_get_by_keyP12memcached_stPKc6size_tPKc6size_tP6size_tP8uint32_tP18memcached_return_t" title=
"memcached_get_by_key"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_get_by_key()
</span></code></a> and
<a class=
"reference internal" href=
"#_CPPv421memcached_mget_by_keyP12memcached_stPKc6size_tPPCKcPK6size_t6size_t" title=
"memcached_mget_by_key"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_mget_by_key()
</span></code></a> behave
308 in a similar nature as
<a class=
"reference internal" href=
"#_CPPv413memcached_getP12memcached_stPKc6size_tP6size_tP8uint32_tP18memcached_return_t" title=
"memcached_get"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_get()
</span></code></a> and
<a class=
"reference internal" href=
"#_CPPv414memcached_mgetP12memcached_stPPCKcPK6size_t6size_t" title=
"memcached_mget"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_mget()
</span></code></a>.
309 The difference is that they take a master key that is used for determining
310 which server an object was stored if key partitioning was used for storage.
</p>
311 <p>All of the above functions are not tested when the
312 <a class=
"reference internal" href=
"memcached_behavior.html#_CPPv4N20memcached_behavior_t26MEMCACHED_BEHAVIOR_USE_UDPE" title=
"MEMCACHED_BEHAVIOR_USE_UDP"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">MEMCACHED_BEHAVIOR_USE_UDP
</span></code></a> has been set. Executing any of these
313 functions with this behavior on will result in
<a class=
"reference internal" href=
"memcached_return_t.html#_CPPv4N18memcached_return_t23MEMCACHED_NOT_SUPPORTEDE" title=
"MEMCACHED_NOT_SUPPORTED"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">MEMCACHED_NOT_SUPPORTED
</span></code></a> being returned, or for those functions which do not return a
<a class=
"reference internal" href=
"memcached_return_t.html#_CPPv418memcached_return_t" title=
"memcached_return_t"><code class=
"xref cpp cpp-type docutils literal notranslate"><span class=
"pre">memcached_return_t
</span></code></a>, the error function parameter will be set to
<a class=
"reference internal" href=
"memcached_return_t.html#_CPPv4N18memcached_return_t23MEMCACHED_NOT_SUPPORTEDE" title=
"MEMCACHED_NOT_SUPPORTED"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">MEMCACHED_NOT_SUPPORTED
</span></code></a>.
</p>
315 <div class=
"section" id=
"return">
316 <h2>RETURN
<a class=
"headerlink" href=
"#return" title=
"Permalink to this headline">¶
</a></h2>
317 <p>All objects retrieved via
<a class=
"reference internal" href=
"#_CPPv413memcached_getP12memcached_stPKc6size_tP6size_tP8uint32_tP18memcached_return_t" title=
"memcached_get"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_get()
</span></code></a> or
<a class=
"reference internal" href=
"#_CPPv420memcached_get_by_keyP12memcached_stPKc6size_tPKc6size_tP6size_tP8uint32_tP18memcached_return_t" title=
"memcached_get_by_key"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_get_by_key()
</span></code></a> must be freed with
<em class=
"manpage"><a class=
"manpage reference external" href=
"http://man7.org/linux/man-pages/man3/free.3.html">free(
3)
</a></em>.
</p>
318 <p><a class=
"reference internal" href=
"#_CPPv413memcached_getP12memcached_stPKc6size_tP6size_tP8uint32_tP18memcached_return_t" title=
"memcached_get"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_get()
</span></code></a> will return NULL on
319 error. You must look at the value of error to determine what the actual error
321 <p><a class=
"reference internal" href=
"#_CPPv423memcached_fetch_executeP12memcached_stP20memcached_execute_fnPv8uint32_t" title=
"memcached_fetch_execute"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_fetch_execute()
</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> if
322 all keys were successful.
<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> will be return if no
323 keys at all were found.
</p>
324 <p><a class=
"reference internal" href=
"#_CPPv422memcached_fetch_resultP12memcached_stP19memcached_result_stP18memcached_return_t" title=
"memcached_fetch_result"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_fetch_result()
</span></code></a> sets error
325 to
<a class=
"reference internal" href=
"memcached_return_t.html#_CPPv4N18memcached_return_t13MEMCACHED_ENDE" title=
"MEMCACHED_END"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">MEMCACHED_END
</span></code></a> upon successful conclusion.
326 <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> will be return if no keys at all were found.
</p>
328 <div class=
"section" id=
"see-also">
329 <h2>SEE ALSO
<a class=
"headerlink" href=
"#see-also" title=
"Permalink to this headline">¶
</a></h2>
339 <div class=
"rst-footer-buttons" role=
"navigation" aria-label=
"footer navigation">
341 <a href=
"memcached_set.html" class=
"btn btn-neutral float-right" title=
"Storing data on the server" accesskey=
"n" rel=
"next">Next
<span class=
"fa fa-arrow-circle-right"></span></a>
344 <a href=
"memcached_create.html" class=
"btn btn-neutral float-left" title=
"Creating and destroying a memcached_st" accesskey=
"p" rel=
"prev"><span class=
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