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</a><ul>
111 <li class=
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</a></li>
115 <p class=
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</span></p>
117 <li class=
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</a></li>
118 <li class=
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</a><ul>
119 <li class=
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</a></li>
120 <li class=
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</a></li>
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</a></li>
126 <p class=
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</span></p>
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</a><ul>
129 <li class=
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"reference internal" href=
"../bin/memcapable.html">memcapable - Checking a Memcached server capabilities and compatibility
</a></li>
130 <li class=
"toctree-l2"><a class=
"reference internal" href=
"../bin/memcat.html">memcat - “cat” data from a server
</a></li>
131 <li class=
"toctree-l2"><a class=
"reference internal" href=
"../bin/memcp.html">memcp - Copy data to a server
</a></li>
132 <li class=
"toctree-l2"><a class=
"reference internal" href=
"../bin/memdump.html">memdump - Dumping your server
</a></li>
133 <li class=
"toctree-l2"><a class=
"reference internal" href=
"../bin/memerror.html">memerror - translate an error code to a string
</a></li>
134 <li class=
"toctree-l2"><a class=
"reference internal" href=
"../bin/memflush.html">memflush - flush all data from a server
</a></li>
135 <li class=
"toctree-l2"><a class=
"reference internal" href=
"../bin/memrm.html">memrm - Remove data from a server
</a></li>
136 <li class=
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"reference internal" href=
"../bin/memslap.html">memslap - Load testing and benchmarking a server
</a></li>
137 <li class=
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"../bin/memaslap.html">memaslap - Load testing and benchmarking a server
</a></li>
138 <li class=
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"../bin/memstat.html">memstat - Gather statistics from a server
</a></li>
139 <li class=
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"../bin/memexist.html">memexist - Check for the existence of a key
</a></li>
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"../bin/memparse.html">memparse - Parse an option string
</a></li>
141 <li class=
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"reference internal" href=
"../bin/memping.html">memping - Test to see if a server is available.
</a></li>
142 <li class=
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</a></li>
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196 <li>Working with statistical information from a server
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213 <div class=
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"working-with-statistical-information-from-a-server">
214 <h1>Working with statistical information from a server
<a class=
"headerlink" href=
"#working-with-statistical-information-from-a-server" title=
"Permalink to this headline">¶
</a></h1>
215 <p>Get memcached statistics
</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>
218 <p>#include
<libmemcached/memcached.h
></p>
220 <dt id=
"_CPPv417memcached_stat_st">
221 <span id=
"_CPPv317memcached_stat_st"></span><span id=
"_CPPv217memcached_stat_st"></span><span id=
"memcached_stat_st"></span><em class=
"property">type
</em><code class=
"sig-name descname">memcached_stat_st
</code><a class=
"headerlink" href=
"#_CPPv417memcached_stat_st" title=
"Permalink to this definition">¶
</a><br /></dt>
225 <dt id=
"_CPPv417memcached_stat_fn">
226 <span id=
"_CPPv317memcached_stat_fn"></span><span id=
"_CPPv217memcached_stat_fn"></span><span id=
"memcached_stat_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_stat_fn
</code>)
<span class=
"sig-paren">(
</span><em class=
"property">const
</em> memcached_instance_st *server,
<em class=
"property">const
</em> char *key, size_t key_length,
<em class=
"property">const
</em> char *value, size_t value_length, void *context
<span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv417memcached_stat_fn" title=
"Permalink to this definition">¶
</a><br /></dt>
229 <dl class=
"function">
230 <dt id=
"_CPPv414memcached_statP12memcached_stPcP18memcached_return_t">
231 <span id=
"_CPPv314memcached_statP12memcached_stPcP18memcached_return_t"></span><span id=
"_CPPv214memcached_statP12memcached_stPcP18memcached_return_t"></span><span id=
"memcached_stat__memcached_stP.cP.memcached_return_tP"></span><a class=
"reference internal" href=
"#_CPPv417memcached_stat_st" title=
"memcached_stat_st">memcached_stat_st
</a> *
<code class=
"sig-name descname">memcached_stat
</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>args
</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=
"#_CPPv414memcached_statP12memcached_stPcP18memcached_return_t" title=
"Permalink to this definition">¶
</a><br /></dt>
234 <dl class=
"function">
235 <dt id=
"_CPPv425memcached_stat_servernameP17memcached_stat_stPcPKc9in_port_t">
236 <span id=
"_CPPv325memcached_stat_servernameP17memcached_stat_stPcPKc9in_port_t"></span><span id=
"_CPPv225memcached_stat_servernameP17memcached_stat_stPcPKc9in_port_t"></span><span id=
"memcached_stat_servername__memcached_stat_stP.cP.cCP.in_port_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_stat_servername
</code><span class=
"sig-paren">(
</span><a class=
"reference internal" href=
"#_CPPv417memcached_stat_st" title=
"memcached_stat_st">memcached_stat_st
</a> *
<em>stat
</em>, char *
<em>args
</em>,
<em class=
"property">const
</em> char *
<em>hostname
</em>, in_port_t
<em>port
</em><span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv425memcached_stat_servernameP17memcached_stat_stPcPKc9in_port_t" title=
"Permalink to this definition">¶
</a><br /></dt>
239 <dl class=
"function">
240 <dt id=
"_CPPv424memcached_stat_get_valueP12memcached_stP17memcached_stat_stPKcP18memcached_return_t">
241 <span id=
"_CPPv324memcached_stat_get_valueP12memcached_stP17memcached_stat_stPKcP18memcached_return_t"></span><span id=
"_CPPv224memcached_stat_get_valueP12memcached_stP17memcached_stat_stPKcP18memcached_return_t"></span><span id=
"memcached_stat_get_value__memcached_stP.memcached_stat_stP.cCP.memcached_return_tP"></span>char *
<code class=
"sig-name descname">memcached_stat_get_value
</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=
"#_CPPv417memcached_stat_st" title=
"memcached_stat_st">memcached_stat_st
</a> *
<em>stat
</em>,
<em class=
"property">const
</em> char *
<em>key
</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=
"#_CPPv424memcached_stat_get_valueP12memcached_stP17memcached_stat_stPKcP18memcached_return_t" title=
"Permalink to this definition">¶
</a><br /></dt>
244 <dl class=
"function">
245 <dt id=
"_CPPv423memcached_stat_get_keysP12memcached_stP17memcached_stat_stP18memcached_return_t">
246 <span id=
"_CPPv323memcached_stat_get_keysP12memcached_stP17memcached_stat_stP18memcached_return_t"></span><span id=
"_CPPv223memcached_stat_get_keysP12memcached_stP17memcached_stat_stP18memcached_return_t"></span><span id=
"memcached_stat_get_keys__memcached_stP.memcached_stat_stP.memcached_return_tP"></span>char **
<code class=
"sig-name descname">memcached_stat_get_keys
</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=
"#_CPPv417memcached_stat_st" title=
"memcached_stat_st">memcached_stat_st
</a> *
<em>stat
</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=
"#_CPPv423memcached_stat_get_keysP12memcached_stP17memcached_stat_stP18memcached_return_t" title=
"Permalink to this definition">¶
</a><br /></dt>
249 <dl class=
"function">
250 <dt id=
"_CPPv422memcached_stat_executeP12memcached_stPKc17memcached_stat_fnPv">
251 <span id=
"_CPPv322memcached_stat_executeP12memcached_stPKc17memcached_stat_fnPv"></span><span id=
"_CPPv222memcached_stat_executeP12memcached_stPKc17memcached_stat_fnPv"></span><span id=
"memcached_stat_execute__memcached_stP.cCP.memcached_stat_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_stat_execute
</code><span class=
"sig-paren">(
</span><a class=
"reference internal" href=
"memcached_create.html#_CPPv412memcached_st" title=
"memcached_st">memcached_st
</a> *
<em>memc
</em>,
<em class=
"property">const
</em> char *
<em>args
</em>,
<a class=
"reference internal" href=
"#_CPPv417memcached_stat_fn" title=
"memcached_stat_fn">memcached_stat_fn
</a> <em>func
</em>, void *
<em>context
</em><span class=
"sig-paren">)
</span><a class=
"headerlink" href=
"#_CPPv422memcached_stat_executeP12memcached_stPKc17memcached_stat_fnPv" title=
"Permalink to this definition">¶
</a><br /></dt>
254 <p>Compile and link with -lmemcached
</p>
256 <div class=
"section" id=
"description">
257 <h2>DESCRIPTION
<a class=
"headerlink" href=
"#description" title=
"Permalink to this headline">¶
</a></h2>
258 <p>libmemcached(
3) has the ability to query a memcached server (or collection
259 of servers) for their current state. Queries to find state return a
260 <a class=
"reference internal" href=
"#_CPPv417memcached_stat_st" title=
"memcached_stat_st"><code class=
"xref cpp cpp-type docutils literal notranslate"><span class=
"pre">memcached_stat_st
</span></code></a> structure. You are responsible for freeing this structure. While it is possible to access the structure directly it is not advisable.
<a class=
"reference internal" href=
"#_CPPv424memcached_stat_get_valueP12memcached_stP17memcached_stat_stPKcP18memcached_return_t" title=
"memcached_stat_get_value"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_stat_get_value()
</span></code></a> has been provided to query the structure.
</p>
261 <p><a class=
"reference internal" href=
"#_CPPv422memcached_stat_executeP12memcached_stPKc17memcached_stat_fnPv" title=
"memcached_stat_execute"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_stat_execute()
</span></code></a> uses the servers found in
<a class=
"reference internal" href=
"#_CPPv417memcached_stat_st" title=
"memcached_stat_st"><code class=
"xref cpp cpp-type docutils literal notranslate"><span class=
"pre">memcached_stat_st
</span></code></a> and executes a “stat” command on each server. args is an optional argument that can be passed in to modify the behavior of “stats”. You will need to supply a callback function that will be supplied each pair of values returned by
262 the memcached server.
</p>
263 <p><a class=
"reference internal" href=
"#_CPPv414memcached_statP12memcached_stPcP18memcached_return_t" title=
"memcached_stat"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_stat()
</span></code></a> fetches an array of
<a class=
"reference internal" href=
"#_CPPv417memcached_stat_st" title=
"memcached_stat_st"><code class=
"xref cpp cpp-type docutils literal notranslate"><span class=
"pre">memcached_stat_st
</span></code></a> structures containing the state of all available memcached servers. The return value must be freed by the calling application. If called with the
<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> behavior set, a NULL value is returned and the error parameter is 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>
264 <p><a class=
"reference internal" href=
"#_CPPv425memcached_stat_servernameP17memcached_stat_stPcPKc9in_port_t" title=
"memcached_stat_servername"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_stat_servername()
</span></code></a> can be used standalone without 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> to obtain the state of a particular server. “args” is used to define a particular state object (a list of these are not provided for by either
265 the
<a class=
"reference internal" href=
"#_CPPv423memcached_stat_get_keysP12memcached_stP17memcached_stat_stP18memcached_return_t" title=
"memcached_stat_get_keys"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_stat_get_keys()
</span></code></a> call nor are they defined in the memcached protocol). You must specify the hostname and port of the server you want to
266 obtain information on.
</p>
267 <p><a class=
"reference internal" href=
"#_CPPv424memcached_stat_get_valueP12memcached_stP17memcached_stat_stPKcP18memcached_return_t" title=
"memcached_stat_get_value"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_stat_get_value()
</span></code></a> returns the value of a particular state key. You specify the key you wish to obtain. The key must be null terminated.
</p>
268 <p><a class=
"reference internal" href=
"#_CPPv423memcached_stat_get_keysP12memcached_stP17memcached_stat_stP18memcached_return_t" title=
"memcached_stat_get_keys"><code class=
"xref cpp cpp-func docutils literal notranslate"><span class=
"pre">memcached_stat_get_keys()
</span></code></a> returns a list of keys that the server has state objects on. You are responsible for freeing this list.
</p>
269 <p>A command line tool, memstat(
1), is provided so that you do not have to write
270 an application to do this.
</p>
272 <div class=
"section" id=
"return">
273 <h2>RETURN
<a class=
"headerlink" href=
"#return" title=
"Permalink to this headline">¶
</a></h2>
274 <p>Varies, see particular functions.
</p>
275 <p>Any method returning a
<a class=
"reference internal" href=
"#_CPPv417memcached_stat_st" title=
"memcached_stat_st"><code class=
"xref cpp cpp-type docutils literal notranslate"><span class=
"pre">memcached_stat_st
</span></code></a> expects you to free the
276 memory allocated for it.
</p>
278 <div class=
"section" id=
"see-also">
279 <h2>SEE ALSO
<a class=
"headerlink" href=
"#see-also" title=
"Permalink to this headline">¶
</a></h2>
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