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196 <li>Setting callbacks
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213 <div class=
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"setting-callbacks">
214 <h1>Setting callbacks
<a class=
"headerlink" href=
"#setting-callbacks" title=
"Permalink to this headline">¶
</a></h1>
215 <p>Get and set a callback
</p>
216 <div class=
"section" id=
"synopsis">
217 <span id=
"index-0"></span><h2>SYNOPSIS
<a class=
"headerlink" href=
"#synopsis" title=
"Permalink to this headline">¶
</a></h2>
219 <dt>#include
<libmemcached/memcached.h
></dt><dd><p>Compile and link with -lmemcached
</p>
222 <dl class=
"function">
223 <dt id=
"_CPPv422memcached_callback_setP12memcached_st20memcached_callback_tPKv">
224 <span id=
"_CPPv322memcached_callback_setP12memcached_st20memcached_callback_tPKv"></span><span id=
"_CPPv222memcached_callback_setP12memcached_st20memcached_callback_tPKv"></span><span id=
"memcached_callback_set__memcached_stP.memcached_callback_t.voidCP"></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_callback_set
</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_callback_t" title=
"memcached_callback_t">memcached_callback_t
</a> <em>flag
</em>,
<em class=
"property">const
</em> void *
<em>data
</em><span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv422memcached_callback_setP12memcached_st20memcached_callback_tPKv" title=
"Permalink to this definition">¶
</a><br /></dt>
227 <dl class=
"function">
228 <dt id=
"_CPPv422memcached_callback_getP12memcached_st20memcached_callback_tP18memcached_return_t">
229 <span id=
"_CPPv322memcached_callback_getP12memcached_st20memcached_callback_tP18memcached_return_t"></span><span id=
"_CPPv222memcached_callback_getP12memcached_st20memcached_callback_tP18memcached_return_t"></span><span id=
"memcached_callback_get__memcached_stP.memcached_callback_t.memcached_return_tP"></span>void *
<code class=
"sig-name descname">memcached_callback_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>,
<a class=
"reference internal" href=
"#_CPPv420memcached_callback_t" title=
"memcached_callback_t">memcached_callback_t
</a> <em>flag
</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_callback_getP12memcached_st20memcached_callback_tP18memcached_return_t" title=
"Permalink to this definition">¶
</a><br /></dt>
233 <dt id=
"c.memcached_callback_t">
234 enum
<a class=
"reference internal" href=
"#c.memcached_callback_t" title=
"memcached_callback_t">memcached_callback_t
</a> <code class=
"sig-name descname">memcached_callback_t
</code><a class=
"headerlink" href=
"#c.memcached_callback_t" title=
"Permalink to this definition">¶
</a></dt>
238 <dt id=
"_CPPv420memcached_callback_t">
239 <span id=
"_CPPv320memcached_callback_t"></span><span id=
"_CPPv220memcached_callback_t"></span><em class=
"property">enum
</em><code class=
"sig-name descname">memcached_callback_t
</code><a class=
"headerlink" href=
"#_CPPv420memcached_callback_t" title=
"Permalink to this definition">¶
</a><br /></dt>
240 <dd><dl class=
"enumerator">
241 <dt id=
"_CPPv4N20memcached_callback_t35MEMCACHED_CALLBACK_CLEANUP_FUNCTIONE">
242 <span id=
"_CPPv3N20memcached_callback_t35MEMCACHED_CALLBACK_CLEANUP_FUNCTIONE"></span><span id=
"_CPPv2N20memcached_callback_t35MEMCACHED_CALLBACK_CLEANUP_FUNCTIONE"></span><em class=
"property">enumerator
</em><code class=
"sig-name descname">MEMCACHED_CALLBACK_CLEANUP_FUNCTION
</code><a class=
"headerlink" href=
"#_CPPv4N20memcached_callback_t35MEMCACHED_CALLBACK_CLEANUP_FUNCTIONE" title=
"Permalink to this definition">¶
</a><br /></dt>
243 <dd><p>When
<a class=
"reference internal" href=
"memcached_delete.html#_CPPv416memcached_deleteP12memcached_stPKc6size_t6time_t" title=
"memcached_delete"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_delete()
</span></code></a> is called this function will be executed. At
244 the point of its execution all connections are closed.
</p>
247 <dl class=
"enumerator">
248 <dt id=
"_CPPv4N20memcached_callback_t33MEMCACHED_CALLBACK_CLONE_FUNCTIONE">
249 <span id=
"_CPPv3N20memcached_callback_t33MEMCACHED_CALLBACK_CLONE_FUNCTIONE"></span><span id=
"_CPPv2N20memcached_callback_t33MEMCACHED_CALLBACK_CLONE_FUNCTIONE"></span><em class=
"property">enumerator
</em><code class=
"sig-name descname">MEMCACHED_CALLBACK_CLONE_FUNCTION
</code><a class=
"headerlink" href=
"#_CPPv4N20memcached_callback_t33MEMCACHED_CALLBACK_CLONE_FUNCTIONE" title=
"Permalink to this definition">¶
</a><br /></dt>
250 <dd><p>When
<a class=
"reference internal" href=
"memcached_delete.html#_CPPv416memcached_deleteP12memcached_stPKc6size_t6time_t" title=
"memcached_delete"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_delete()
</span></code></a> is called this function will be executed.
251 At the point of its execution all connections are closed.
</p>
254 <dl class=
"enumerator">
255 <dt id=
"_CPPv4N20memcached_callback_t29MEMCACHED_CALLBACK_PREFIX_KEYE">
256 <span id=
"_CPPv3N20memcached_callback_t29MEMCACHED_CALLBACK_PREFIX_KEYE"></span><span id=
"_CPPv2N20memcached_callback_t29MEMCACHED_CALLBACK_PREFIX_KEYE"></span><em class=
"property">enumerator
</em><code class=
"sig-name descname">MEMCACHED_CALLBACK_PREFIX_KEY
</code><a class=
"headerlink" href=
"#_CPPv4N20memcached_callback_t29MEMCACHED_CALLBACK_PREFIX_KEYE" title=
"Permalink to this definition">¶
</a><br /></dt>
257 <dd><p>See
<a class=
"reference internal" href=
"#_CPPv4N20memcached_callback_t28MEMCACHED_CALLBACK_NAMESPACEE" title=
"memcached_callback_t::MEMCACHED_CALLBACK_NAMESPACE"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">MEMCACHED_CALLBACK_NAMESPACE
</span></code></a></p>
260 <dl class=
"enumerator">
261 <dt id=
"_CPPv4N20memcached_callback_t28MEMCACHED_CALLBACK_NAMESPACEE">
262 <span id=
"_CPPv3N20memcached_callback_t28MEMCACHED_CALLBACK_NAMESPACEE"></span><span id=
"_CPPv2N20memcached_callback_t28MEMCACHED_CALLBACK_NAMESPACEE"></span><em class=
"property">enumerator
</em><code class=
"sig-name descname">MEMCACHED_CALLBACK_NAMESPACE
</code><a class=
"headerlink" href=
"#_CPPv4N20memcached_callback_t28MEMCACHED_CALLBACK_NAMESPACEE" title=
"Permalink to this definition">¶
</a><br /></dt>
263 <dd><p>You can set a value which will be used to create a domain for your keys.
264 The value specified here will be prefixed to each of your keys. The value can
265 not be greater then
<code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">MEMCACHED_PREFIX_KEY_MAX_SIZE
</span></code> -
1 and will
266 reduce
<code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">MEMCACHED_MAX_KEY
</span></code> by the value of your key.
</p>
267 <p>The prefix key is only applied to the primary key, not the master key.
268 <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> will be returned if no key is set. In the case of
269 a key which is too long,
<a class=
"reference internal" href=
"memcached_return_t.html#_CPPv4N18memcached_return_t26MEMCACHED_BAD_KEY_PROVIDEDE" title=
"MEMCACHED_BAD_KEY_PROVIDED"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">MEMCACHED_BAD_KEY_PROVIDED
</span></code></a> will be returned.
</p>
270 <p>If you set a value with the value being NULL then the prefix key is disabled.
</p>
273 <dl class=
"enumerator">
274 <dt id=
"_CPPv4N20memcached_callback_t28MEMCACHED_CALLBACK_USER_DATAE">
275 <span id=
"_CPPv3N20memcached_callback_t28MEMCACHED_CALLBACK_USER_DATAE"></span><span id=
"_CPPv2N20memcached_callback_t28MEMCACHED_CALLBACK_USER_DATAE"></span><em class=
"property">enumerator
</em><code class=
"sig-name descname">MEMCACHED_CALLBACK_USER_DATA
</code><a class=
"headerlink" href=
"#_CPPv4N20memcached_callback_t28MEMCACHED_CALLBACK_USER_DATAE" title=
"Permalink to this definition">¶
</a><br /></dt>
276 <dd><p>This allows you to store a pointer to a specific piece of data. This can be
277 retrieved from inside of
<a class=
"reference internal" href=
"memcached_get.html#_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>. Cloning a
278 <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> will copy the pointer to the clone.
</p>
281 <dl class=
"enumerator">
282 <dt id=
"_CPPv4N20memcached_callback_t34MEMCACHED_CALLBACK_MALLOC_FUNCTIONE">
283 <span id=
"_CPPv3N20memcached_callback_t34MEMCACHED_CALLBACK_MALLOC_FUNCTIONE"></span><span id=
"_CPPv2N20memcached_callback_t34MEMCACHED_CALLBACK_MALLOC_FUNCTIONE"></span><em class=
"property">enumerator
</em><code class=
"sig-name descname">MEMCACHED_CALLBACK_MALLOC_FUNCTION
</code><a class=
"headerlink" href=
"#_CPPv4N20memcached_callback_t34MEMCACHED_CALLBACK_MALLOC_FUNCTIONE" title=
"Permalink to this definition">¶
</a><br /></dt>
284 <dd><div class=
"deprecated">
285 <p><span class=
"versionmodified deprecated">Deprecated since version
<0.32:
</span>Use
<a class=
"reference internal" href=
"memcached_memory_allocators.html#_CPPv431memcached_set_memory_allocatorsP12memcached_st19memcached_malloc_fn17memcached_free_fn20memcached_realloc_fn19memcached_calloc_fnPv" title=
"memcached_set_memory_allocators"><code class=
"xref cpp cpp-type docutils literal notranslate"><span class=
"pre">memcached_set_memory_allocators
</span></code></a> instead.
</p>
289 <dl class=
"enumerator">
290 <dt id=
"_CPPv4N20memcached_callback_t35MEMCACHED_CALLBACK_REALLOC_FUNCTIONE">
291 <span id=
"_CPPv3N20memcached_callback_t35MEMCACHED_CALLBACK_REALLOC_FUNCTIONE"></span><span id=
"_CPPv2N20memcached_callback_t35MEMCACHED_CALLBACK_REALLOC_FUNCTIONE"></span><em class=
"property">enumerator
</em><code class=
"sig-name descname">MEMCACHED_CALLBACK_REALLOC_FUNCTION
</code><a class=
"headerlink" href=
"#_CPPv4N20memcached_callback_t35MEMCACHED_CALLBACK_REALLOC_FUNCTIONE" title=
"Permalink to this definition">¶
</a><br /></dt>
292 <dd><div class=
"deprecated">
293 <p><span class=
"versionmodified deprecated">Deprecated since version
<0.32:
</span>Use
<a class=
"reference internal" href=
"memcached_memory_allocators.html#_CPPv431memcached_set_memory_allocatorsP12memcached_st19memcached_malloc_fn17memcached_free_fn20memcached_realloc_fn19memcached_calloc_fnPv" title=
"memcached_set_memory_allocators"><code class=
"xref cpp cpp-type docutils literal notranslate"><span class=
"pre">memcached_set_memory_allocators
</span></code></a> instead.
</p>
297 <dl class=
"enumerator">
298 <dt id=
"_CPPv4N20memcached_callback_t32MEMCACHED_CALLBACK_FREE_FUNCTIONE">
299 <span id=
"_CPPv3N20memcached_callback_t32MEMCACHED_CALLBACK_FREE_FUNCTIONE"></span><span id=
"_CPPv2N20memcached_callback_t32MEMCACHED_CALLBACK_FREE_FUNCTIONE"></span><em class=
"property">enumerator
</em><code class=
"sig-name descname">MEMCACHED_CALLBACK_FREE_FUNCTION
</code><a class=
"headerlink" href=
"#_CPPv4N20memcached_callback_t32MEMCACHED_CALLBACK_FREE_FUNCTIONE" title=
"Permalink to this definition">¶
</a><br /></dt>
300 <dd><div class=
"deprecated">
301 <p><span class=
"versionmodified deprecated">Deprecated since version
<0.32:
</span>Use
<a class=
"reference internal" href=
"memcached_memory_allocators.html#_CPPv431memcached_set_memory_allocatorsP12memcached_st19memcached_malloc_fn17memcached_free_fn20memcached_realloc_fn19memcached_calloc_fnPv" title=
"memcached_set_memory_allocators"><code class=
"xref cpp cpp-type docutils literal notranslate"><span class=
"pre">memcached_set_memory_allocators
</span></code></a> instead.
</p>
305 <dl class=
"enumerator">
306 <dt id=
"_CPPv4N20memcached_callback_t30MEMCACHED_CALLBACK_GET_FAILUREE">
307 <span id=
"_CPPv3N20memcached_callback_t30MEMCACHED_CALLBACK_GET_FAILUREE"></span><span id=
"_CPPv2N20memcached_callback_t30MEMCACHED_CALLBACK_GET_FAILUREE"></span><em class=
"property">enumerator
</em><code class=
"sig-name descname">MEMCACHED_CALLBACK_GET_FAILURE
</code><a class=
"headerlink" href=
"#_CPPv4N20memcached_callback_t30MEMCACHED_CALLBACK_GET_FAILUREE" title=
"Permalink to this definition">¶
</a><br /></dt>
308 <dd><p>This function implements the read through cache behavior. On failure of retrieval this callback will be called.
</p>
309 <p>You are responsible for populating the result object provided. This result object will then be stored in the server and returned to the calling process.
</p>
310 <p>You must clone the
<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> in order to
311 make use of it. The value will be stored only if you return
312 <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> or
<a class=
"reference internal" href=
"memcached_return_t.html#_CPPv4N18memcached_return_t18MEMCACHED_BUFFEREDE" title=
"MEMCACHED_BUFFERED"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">MEMCACHED_BUFFERED
</span></code></a>. Returning
313 <a class=
"reference internal" href=
"memcached_return_t.html#_CPPv4N18memcached_return_t18MEMCACHED_BUFFEREDE" title=
"MEMCACHED_BUFFERED"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">MEMCACHED_BUFFERED
</span></code></a> will cause the object to be buffered and not sent
314 immediately (if this is the default behavior based on your connection setup
315 this will happen automatically).
</p>
316 <p>The prototype for this is:
</p>
318 <dt id=
"_CPPv4N20memcached_callback_t30MEMCACHED_CALLBACK_GET_FAILURE21memcached_trigger_keyE">
319 <span id=
"_CPPv3N20memcached_callback_t30MEMCACHED_CALLBACK_GET_FAILURE21memcached_trigger_keyE"></span><span id=
"_CPPv2N20memcached_callback_t30MEMCACHED_CALLBACK_GET_FAILURE21memcached_trigger_keyE"></span><span id=
"memcached_callback_t::MEMCACHED_CALLBACK_GET_FAILURE::memcached_trigger_key"></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_trigger_key
</code>)
<span class=
"sig-paren">(
</span><a class=
"reference internal" href=
"memcached_create.html#_CPPv412memcached_st" title=
"memcached_st">memcached_st
</a> *ptr, char *key, size_t key_length,
<a class=
"reference internal" href=
"memcached_result_st.html#_CPPv419memcached_result_st" title=
"memcached_result_st">memcached_result_st
</a> *result
<span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv4N20memcached_callback_t30MEMCACHED_CALLBACK_GET_FAILURE21memcached_trigger_keyE" title=
"Permalink to this definition">¶
</a><br /></dt>
324 <dl class=
"enumerator">
325 <dt id=
"_CPPv4N20memcached_callback_t33MEMCACHED_CALLBACK_DELETE_TRIGGERE">
326 <span id=
"_CPPv3N20memcached_callback_t33MEMCACHED_CALLBACK_DELETE_TRIGGERE"></span><span id=
"_CPPv2N20memcached_callback_t33MEMCACHED_CALLBACK_DELETE_TRIGGERE"></span><em class=
"property">enumerator
</em><code class=
"sig-name descname">MEMCACHED_CALLBACK_DELETE_TRIGGER
</code><a class=
"headerlink" href=
"#_CPPv4N20memcached_callback_t33MEMCACHED_CALLBACK_DELETE_TRIGGERE" title=
"Permalink to this definition">¶
</a><br /></dt>
327 <dd><p>This function implements a trigger upon successful deletion of a key. The memcached_st structure will need to be cloned in order to make use of it.
</p>
328 <p>The prototype for this is:
</p>
330 <dt id=
"_CPPv4N20memcached_callback_t33MEMCACHED_CALLBACK_DELETE_TRIGGER28memcached_trigger_delete_keyE">
331 <span id=
"_CPPv3N20memcached_callback_t33MEMCACHED_CALLBACK_DELETE_TRIGGER28memcached_trigger_delete_keyE"></span><span id=
"_CPPv2N20memcached_callback_t33MEMCACHED_CALLBACK_DELETE_TRIGGER28memcached_trigger_delete_keyE"></span><span id=
"memcached_callback_t::MEMCACHED_CALLBACK_DELETE_TRIGGER::memcached_trigger_delete_key"></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_trigger_delete_key
</code>)
<span class=
"sig-paren">(
</span><a class=
"reference internal" href=
"memcached_create.html#_CPPv412memcached_st" title=
"memcached_st">memcached_st
</a> *ptr, char *key, size_t key_length
<span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv4N20memcached_callback_t33MEMCACHED_CALLBACK_DELETE_TRIGGER28memcached_trigger_delete_keyE" title=
"Permalink to this definition">¶
</a><br /></dt>
339 <div class=
"section" id=
"description">
340 <h2>DESCRIPTION
<a class=
"headerlink" href=
"#description" title=
"Permalink to this headline">¶
</a></h2>
341 <p><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">libmemcached
</span></code> can have callbacks set key execution points. These either
342 provide function calls at points in the code, or return pointers to
343 structures for particular usages.
</p>
344 <p><a class=
"reference internal" href=
"#_CPPv422memcached_callback_getP12memcached_st20memcached_callback_tP18memcached_return_t" title=
"memcached_callback_get"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_callback_get()
</span></code></a> takes a callback flag and returns the
345 structure or function set by
<a class=
"reference internal" href=
"#_CPPv422memcached_callback_setP12memcached_st20memcached_callback_tPKv" title=
"memcached_callback_set"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_callback_set()
</span></code></a>.
</p>
346 <p><a class=
"reference internal" href=
"#_CPPv422memcached_callback_setP12memcached_st20memcached_callback_tPKv" title=
"memcached_callback_set"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_callback_set()
</span></code></a> changes the function/structure assigned by a
347 callback flag. No connections are reset.
</p>
348 <p>You can use
<a class=
"reference internal" href=
"#_CPPv4N20memcached_callback_t28MEMCACHED_CALLBACK_USER_DATAE" title=
"MEMCACHED_CALLBACK_USER_DATA"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">MEMCACHED_CALLBACK_USER_DATA
</span></code></a> to provide custom context
349 if required for any of the callbacks.
</p>
351 <div class=
"section" id=
"return-value">
352 <h2>RETURN VALUE
<a class=
"headerlink" href=
"#return-value" title=
"Permalink to this headline">¶
</a></h2>
353 <p><a class=
"reference internal" href=
"#_CPPv422memcached_callback_getP12memcached_st20memcached_callback_tP18memcached_return_t" title=
"memcached_callback_get"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_callback_get()
</span></code></a> return the function or structure that was
354 provided. Upon error, nothing is set, null is returned, and the
355 <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> argument is set to
<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>.
</p>
356 <p><a class=
"reference internal" href=
"#_CPPv422memcached_callback_setP12memcached_st20memcached_callback_tPKv" title=
"memcached_callback_set"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_callback_set()
</span></code></a> returns
<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
357 successful setting, otherwise
<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> on error.
</p>
359 <div class=
"section" id=
"see-also">
360 <h2>SEE ALSO
<a class=
"headerlink" href=
"#see-also" title=
"Permalink to this headline">¶
</a></h2>
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"rst-footer-buttons" role=
"navigation" aria-label=
"footer navigation">
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