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176 <li>Incrementing and Decrementing Values
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193 <div class=
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194 <h1>Incrementing and Decrementing Values
<a class=
"headerlink" href=
"#incrementing-and-decrementing-values" title=
"Permalink to this headline">¶
</a></h1>
195 <div class=
"section" id=
"synopsis">
196 <h2>SYNOPSIS
<a class=
"headerlink" href=
"#synopsis" title=
"Permalink to this headline">¶
</a></h2>
197 <dl class=
"docutils">
198 <dt>#include
<libmemcached/memcached.h
></dt>
199 <dd>Compile and link with -lmemcached
</dd>
201 <dl class=
"function">
202 <dt id=
"_CPPv419memcached_incrementP12memcached_stPKc6size_t8uint32_tP8uint64_t">
203 <span id=
"_CPPv319memcached_incrementP12memcached_stPKc6size_t8uint32_tP8uint64_t"></span><span id=
"_CPPv219memcached_incrementP12memcached_stPKc6size_t8uint32_tP8uint64_t"></span><span id=
"memcached_increment__memcached_stP.cCP.s.uint32_t.uint64_tP"></span><a class=
"reference internal" href=
"memcached_return_t.html#_CPPv418memcached_return_t" title=
"memcached_return_t">memcached_return_t
</a> <code class=
"descname">memcached_increment
</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>, uint32_t
<em>offset
</em>, uint64_t *
<em>value
</em><span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv419memcached_incrementP12memcached_stPKc6size_t8uint32_tP8uint64_t" title=
"Permalink to this definition">¶
</a><br /></dt>
206 <dl class=
"function">
207 <dt id=
"_CPPv419memcached_decrementP12memcached_stPKc6size_t8uint32_tP8uint64_t">
208 <span id=
"_CPPv319memcached_decrementP12memcached_stPKc6size_t8uint32_tP8uint64_t"></span><span id=
"_CPPv219memcached_decrementP12memcached_stPKc6size_t8uint32_tP8uint64_t"></span><span id=
"memcached_decrement__memcached_stP.cCP.s.uint32_t.uint64_tP"></span><a class=
"reference internal" href=
"memcached_return_t.html#_CPPv418memcached_return_t" title=
"memcached_return_t">memcached_return_t
</a> <code class=
"descname">memcached_decrement
</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>, uint32_t
<em>offset
</em>, uint64_t *
<em>value
</em><span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv419memcached_decrementP12memcached_stPKc6size_t8uint32_tP8uint64_t" title=
"Permalink to this definition">¶
</a><br /></dt>
211 <dl class=
"function">
212 <dt id=
"_CPPv432memcached_increment_with_initialP12memcached_stPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t">
213 <span id=
"_CPPv332memcached_increment_with_initialP12memcached_stPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t"></span><span id=
"_CPPv232memcached_increment_with_initialP12memcached_stPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t"></span><span id=
"memcached_increment_with_initial__memcached_stP.cCP.s.uint64_t.uint64_t.time_t.uint64_tP"></span><a class=
"reference internal" href=
"memcached_return_t.html#_CPPv418memcached_return_t" title=
"memcached_return_t">memcached_return_t
</a> <code class=
"descname">memcached_increment_with_initial
</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>, uint64_t
<em>offset
</em>, uint64_t
<em>initial
</em>, time_t
<em>expiration
</em>, uint64_t *
<em>value
</em><span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv432memcached_increment_with_initialP12memcached_stPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t" title=
"Permalink to this definition">¶
</a><br /></dt>
216 <dl class=
"function">
217 <dt id=
"_CPPv432memcached_decrement_with_initialP12memcached_stPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t">
218 <span id=
"_CPPv332memcached_decrement_with_initialP12memcached_stPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t"></span><span id=
"_CPPv232memcached_decrement_with_initialP12memcached_stPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t"></span><span id=
"memcached_decrement_with_initial__memcached_stP.cCP.s.uint64_t.uint64_t.time_t.uint64_tP"></span><a class=
"reference internal" href=
"memcached_return_t.html#_CPPv418memcached_return_t" title=
"memcached_return_t">memcached_return_t
</a> <code class=
"descname">memcached_decrement_with_initial
</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>, uint64_t
<em>offset
</em>, uint64_t
<em>initial
</em>, time_t
<em>expiration
</em>, uint64_t *
<em>value
</em><span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv432memcached_decrement_with_initialP12memcached_stPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t" title=
"Permalink to this definition">¶
</a><br /></dt>
221 <dl class=
"function">
222 <dt id=
"_CPPv426memcached_increment_by_keyP12memcached_stPKc6size_tPKc6size_t8uint32_tP8uint64_t">
223 <span id=
"_CPPv326memcached_increment_by_keyP12memcached_stPKc6size_tPKc6size_t8uint32_tP8uint64_t"></span><span id=
"_CPPv226memcached_increment_by_keyP12memcached_stPKc6size_tPKc6size_t8uint32_tP8uint64_t"></span><span id=
"memcached_increment_by_key__memcached_stP.cCP.s.cCP.s.uint32_t.uint64_tP"></span><a class=
"reference internal" href=
"memcached_return_t.html#_CPPv418memcached_return_t" title=
"memcached_return_t">memcached_return_t
</a> <code class=
"descname">memcached_increment_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>, uint32_t
<em>offset
</em>, uint64_t *
<em>value
</em><span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv426memcached_increment_by_keyP12memcached_stPKc6size_tPKc6size_t8uint32_tP8uint64_t" title=
"Permalink to this definition">¶
</a><br /></dt>
226 <dl class=
"function">
227 <dt id=
"_CPPv426memcached_decrement_by_keyP12memcached_stPKc6size_tPKc6size_t8uint32_tP8uint64_t">
228 <span id=
"_CPPv326memcached_decrement_by_keyP12memcached_stPKc6size_tPKc6size_t8uint32_tP8uint64_t"></span><span id=
"_CPPv226memcached_decrement_by_keyP12memcached_stPKc6size_tPKc6size_t8uint32_tP8uint64_t"></span><span id=
"memcached_decrement_by_key__memcached_stP.cCP.s.cCP.s.uint32_t.uint64_tP"></span><a class=
"reference internal" href=
"memcached_return_t.html#_CPPv418memcached_return_t" title=
"memcached_return_t">memcached_return_t
</a> <code class=
"descname">memcached_decrement_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>, uint32_t
<em>offset
</em>, uint64_t *
<em>value
</em><span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv426memcached_decrement_by_keyP12memcached_stPKc6size_tPKc6size_t8uint32_tP8uint64_t" title=
"Permalink to this definition">¶
</a><br /></dt>
231 <dl class=
"function">
232 <dt id=
"_CPPv439memcached_increment_with_initial_by_keyP12memcached_stPKc6size_tPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t">
233 <span id=
"_CPPv339memcached_increment_with_initial_by_keyP12memcached_stPKc6size_tPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t"></span><span id=
"_CPPv239memcached_increment_with_initial_by_keyP12memcached_stPKc6size_tPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t"></span><span id=
"memcached_increment_with_initial_by_key__memcached_stP.cCP.s.cCP.s.uint64_t.uint64_t.time_t.uint64_tP"></span><a class=
"reference internal" href=
"memcached_return_t.html#_CPPv418memcached_return_t" title=
"memcached_return_t">memcached_return_t
</a> <code class=
"descname">memcached_increment_with_initial_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>, uint64_t
<em>offset
</em>, uint64_t
<em>initial
</em>, time_t
<em>expiration
</em>, uint64_t *
<em>value
</em><span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv439memcached_increment_with_initial_by_keyP12memcached_stPKc6size_tPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t" title=
"Permalink to this definition">¶
</a><br /></dt>
236 <dl class=
"function">
237 <dt id=
"_CPPv439memcached_decrement_with_initial_by_keyP12memcached_stPKc6size_tPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t">
238 <span id=
"_CPPv339memcached_decrement_with_initial_by_keyP12memcached_stPKc6size_tPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t"></span><span id=
"_CPPv239memcached_decrement_with_initial_by_keyP12memcached_stPKc6size_tPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t"></span><span id=
"memcached_decrement_with_initial_by_key__memcached_stP.cCP.s.cCP.s.uint64_t.uint64_t.time_t.uint64_tP"></span><a class=
"reference internal" href=
"memcached_return_t.html#_CPPv418memcached_return_t" title=
"memcached_return_t">memcached_return_t
</a> <code class=
"descname">memcached_decrement_with_initial_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>, uint64_t
<em>offset
</em>, uint64_t
<em>initial
</em>, time_t
<em>expiration
</em>, uint64_t *
<em>value
</em><span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv439memcached_decrement_with_initial_by_keyP12memcached_stPKc6size_tPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t" title=
"Permalink to this definition">¶
</a><br /></dt>
239 <dd><table class=
"docutils field-list" frame=
"void" rules=
"none">
240 <col class=
"field-name" />
241 <col class=
"field-body" />
243 <tr class=
"field-odd field"><th class=
"field-name">Parameters:
</th><td class=
"field-body"><ul class=
"first simple">
244 <li><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
</li>
245 <li><strong>group_key
</strong> -- key namespace
</li>
246 <li><strong>group_key_length
</strong> -- length of the key namespace without any terminating zero
</li>
247 <li><strong>key
</strong> -- the key
</li>
248 <li><strong>key_length
</strong> -- length of the key without any terminating zero
</li>
249 <li><strong>offset
</strong> -- offset to increment/decrement
</li>
250 <li><strong>initial
</strong> -- initial value if
<a class=
"reference internal" href=
"#_CPPv439memcached_decrement_with_initial_by_keyP12memcached_stPKc6size_tPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t" title=
"memcached_decrement_with_initial_by_key::key"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">key
</span></code></a> does not exist and
<a class=
"reference internal" href=
"#_CPPv439memcached_decrement_with_initial_by_keyP12memcached_stPKc6size_tPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t" title=
"memcached_decrement_with_initial_by_key::expiration"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">expiration
</span></code></a> is not
<code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">MEMCACHED_EXPIRATION_NOT_ADD
</span></code></li>
251 <li><strong>expiration
</strong> -- expiration as a unix timestamp or as relative expiration time in seconds
</li>
252 <li><strong>value
</strong> -- the resulting value after initialization/increment/decrement
</li>
256 <tr class=
"field-even field"><th class=
"field-name">Returns:
</th><td class=
"field-body"><p class=
"first last"><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>
264 <div class=
"section" id=
"description">
265 <h2>DESCRIPTION
<a class=
"headerlink" href=
"#description" title=
"Permalink to this headline">¶
</a></h2>
266 <p><em class=
"manpage"><a class=
"manpage reference external" href=
"https://linux.die.net/man/1/memcached">memcached(
1)
</a></em> servers have the ability to increment and decrement keys
267 (overflow and underflow are not detected). This gives you the ability to use
268 memcached to generate shared sequences of values.
</p>
269 <p><a class=
"reference internal" href=
"#_CPPv419memcached_incrementP12memcached_stPKc6size_t8uint32_tP8uint64_t" title=
"memcached_increment"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">memcached_increment()
</span></code></a> takes a
<code class=
"docutils literal notranslate"><span class=
"pre">key
</span></code> and
<code class=
"docutils literal notranslate"><span class=
"pre">key_length
</span></code> and increments the
270 value by the
<code class=
"docutils literal notranslate"><span class=
"pre">offset
</span></code> passed to it. The value is then returned via the
271 uint32_t
<code class=
"docutils literal notranslate"><span class=
"pre">value
</span></code> pointer you pass to it.
</p>
272 <p><a class=
"reference internal" href=
"#_CPPv419memcached_decrementP12memcached_stPKc6size_t8uint32_tP8uint64_t" title=
"memcached_decrement"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">memcached_decrement()
</span></code></a> takes a
<code class=
"docutils literal notranslate"><span class=
"pre">key
</span></code> and
<code class=
"docutils literal notranslate"><span class=
"pre">key_length
</span></code> and decrements the
273 value by the
<code class=
"docutils literal notranslate"><span class=
"pre">offset
</span></code> passed to it. The value is then returned via the
274 uint32_t
<code class=
"docutils literal notranslate"><span class=
"pre">value
</span></code> pointer you pass to it.
</p>
275 <p><a class=
"reference internal" href=
"#_CPPv432memcached_increment_with_initialP12memcached_stPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t" title=
"memcached_increment_with_initial"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">memcached_increment_with_initial()
</span></code></a> takes a
<code class=
"docutils literal notranslate"><span class=
"pre">key
</span></code> and
<code class=
"docutils literal notranslate"><span class=
"pre">key_length
</span></code> and
276 increments the value by the
<code class=
"docutils literal notranslate"><span class=
"pre">offset
</span></code> passed to it. If the object specified by
277 <code class=
"docutils literal notranslate"><span class=
"pre">key
</span></code> does not exist, one of two things may happen: If the
<code class=
"docutils literal notranslate"><span class=
"pre">expiration
</span></code>
278 value is
<a class=
"reference internal" href=
"constants.html#c.MEMCACHED_EXPIRATION_NOT_ADD" title=
"MEMCACHED_EXPIRATION_NOT_ADD"><code class=
"xref c c-macro docutils literal notranslate"><span class=
"pre">MEMCACHED_EXPIRATION_NOT_ADD
</span></code></a>, the operation will fail. For
279 all other
<code class=
"docutils literal notranslate"><span class=
"pre">expiration
</span></code> values, the operation will succeed by seeding the value
280 for that key with a initial value to expire with the provided expiration time.
281 The
<code class=
"docutils literal notranslate"><span class=
"pre">flags
</span></code> will be set to zero. The value is then returned via the uint32_t
282 <code class=
"docutils literal notranslate"><span class=
"pre">value
</span></code> pointer you pass to it.
<code class=
"docutils literal notranslate"><span class=
"pre">memcached_increment_with_initial
</span></code> is only
283 available when using the binary protocol.
</p>
284 <p><a class=
"reference internal" href=
"#_CPPv432memcached_decrement_with_initialP12memcached_stPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t" title=
"memcached_decrement_with_initial"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">memcached_decrement_with_initial()
</span></code></a> takes a
<code class=
"docutils literal notranslate"><span class=
"pre">key
</span></code> and
<code class=
"docutils literal notranslate"><span class=
"pre">key_length
</span></code> and
285 decrements the value by the
<code class=
"docutils literal notranslate"><span class=
"pre">offset
</span></code> passed to it. If the object specified by
286 <code class=
"docutils literal notranslate"><span class=
"pre">key
</span></code> does not exist, one of two things may happen: If the
<code class=
"docutils literal notranslate"><span class=
"pre">expiration
</span></code>
287 value is
<a class=
"reference internal" href=
"constants.html#c.MEMCACHED_EXPIRATION_NOT_ADD" title=
"MEMCACHED_EXPIRATION_NOT_ADD"><code class=
"xref c c-macro docutils literal notranslate"><span class=
"pre">MEMCACHED_EXPIRATION_NOT_ADD
</span></code></a>, the operation will fail. For
288 all other
<code class=
"docutils literal notranslate"><span class=
"pre">expiration
</span></code> values, the operation will succeed by seeding the value
289 for that key with a initial value to expire with the provided expiration time.
290 The
<code class=
"docutils literal notranslate"><span class=
"pre">flags
</span></code> will be set to zero. The value is then returned via the uint32_t
291 <code class=
"docutils literal notranslate"><span class=
"pre">value
</span></code> pointer you pass to it.
<a class=
"reference internal" href=
"#_CPPv432memcached_decrement_with_initialP12memcached_stPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t" title=
"memcached_decrement_with_initial"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">memcached_decrement_with_initial()
</span></code></a> is only
292 available when using the binary protocol.
</p>
293 <p><a class=
"reference internal" href=
"#_CPPv426memcached_increment_by_keyP12memcached_stPKc6size_tPKc6size_t8uint32_tP8uint64_t" title=
"memcached_increment_by_key"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">memcached_increment_by_key()
</span></code></a>,
<a class=
"reference internal" href=
"#_CPPv426memcached_decrement_by_keyP12memcached_stPKc6size_tPKc6size_t8uint32_tP8uint64_t" title=
"memcached_decrement_by_key"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">memcached_decrement_by_key()
</span></code></a>,
294 <a class=
"reference internal" href=
"#_CPPv439memcached_increment_with_initial_by_keyP12memcached_stPKc6size_tPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t" title=
"memcached_increment_with_initial_by_key"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">memcached_increment_with_initial_by_key()
</span></code></a>, and
295 <a class=
"reference internal" href=
"#_CPPv439memcached_decrement_with_initial_by_keyP12memcached_stPKc6size_tPKc6size_t8uint64_t8uint64_t6time_tP8uint64_t" title=
"memcached_decrement_with_initial_by_key"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">memcached_decrement_with_initial_by_key()
</span></code></a> are master key equivalents of the
298 <div class=
"section" id=
"return-value">
299 <h2>RETURN VALUE
<a class=
"headerlink" href=
"#return-value" title=
"Permalink to this headline">¶
</a></h2>
300 <p>A value of type
<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> is returned.
301 On success that value will be
<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>.
302 Use
<a class=
"reference internal" href=
"memcached_strerror.html#_CPPv418memcached_strerrorP12memcached_st18memcached_return_t" title=
"memcached_strerror"><code class=
"xref cpp cpp-any docutils literal notranslate"><span class=
"pre">memcached_strerror()
</span></code></a> to translate this value to a printable string.
</p>
304 <div class=
"section" id=
"see-also">
305 <h2>SEE ALSO
<a class=
"headerlink" href=
"#see-also" title=
"Permalink to this headline">¶
</a></h2>
307 <li><em class=
"manpage"><a class=
"manpage reference external" href=
"https://linux.die.net/man/1/memcached">memcached(
1)
</a></em></li>
308 <li><a class=
"reference internal" href=
"../libmemcached.html"><span class=
"doc">C/C++ Client Library for memcached
</span></a></li>
309 <li><a class=
"reference internal" href=
"memcached_strerror.html"><span class=
"doc">Converting Error Codes to Messages
</span></a></li>
320 <div class=
"rst-footer-buttons" role=
"navigation" aria-label=
"footer navigation">
322 <a href=
"memcached_exist.html" class=
"btn btn-neutral float-right" title=
"Determine if a keys exists" accesskey=
"n" rel=
"next">Next
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"fa fa-arrow-circle-right"></span></a>
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"index_data.html" class=
"btn btn-neutral float-left" title=
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