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<TITLE>Example - Simple Cache</TITLE>
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<P>Slide 40 of 77</P>
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<H2>Example - Simple Cache</H2>
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<P><UL>
<LI><H2>nsv and ns_mutex can implement a simple cache:</H2>
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proc cache.get {key} {
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set lock [nsv_get cache lock]
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ns_mutex lock $lock
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if ![nsv_exists cache value,$key] {
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nsv_set cache $key [ fetch data for $key ]
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}
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set value [nsv_get cache $key]
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ns_mutex unlock $lock
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return $value
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}</UL></P>
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