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<th width="60%" align="center">Chapter 1.
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<h2 class="title" style="clear: both"><a id="stldbstl_global_functionsopen_env"></a>open_env</h2>
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<pre class="programlisting">
DbEnv* open_env(const char *env_home, u_int32_t set_flags,
u_int32_t oflags=DB_CREATE|DB_INIT_MPOOL,
u_int32_t cachesize=4 *1024 *1024, int mode=0644,
u_int32_t cflags=0)
</pre>
<p>Helper function to open an environment and register it into dbstl for the calling thread. </p>
<p>Users still need to register it in any other thread if it is shared by multiple threads, via <a class="link" href="stldbstl_global_functionsregister_db_env.html" title="register_db_env">register_db_env()</a>
function above. Users don't need to delete or free the memory of the returned object, dbstl will take care of that.</p>
<p>When you don't use <a class="link" href="stldbstl_global_functionsopen_env.html" title="open_env">dbstl::open_env()</a>
but explicitly call DB C++ API to open an environment, you must new the DbEnv object, rather than create it on stack, and you must delete the DbEnv object by yourself. </p>
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<h4 class="title"><a id="id3913193"></a>Parameters</h4>
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<h5 class="title"><a id="id3913196"></a>oflags</h5>
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<p>Environment open flags, passed to DbEnv::open. </p>
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<h5 class="title"><a id="id3913228"></a>set_flags</h5>
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<p>Flags to set to the created environment before opening it. </p>
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<h5 class="title"><a id="id3913234"></a>mode</h5>
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<p>Environment region files mode, passed to DbEnv::open. </p>
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<h5 class="title"><a id="id3913241"></a>cflags</h5>
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<p>DbEnv constructor creation flags, passed to DbEnv::DbEnv. </p>
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<h5 class="title"><a id="id3913247"></a>cachesize</h5>
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<p>Environment cache size, by default 4M bytes. </p>
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<h5 class="title"><a id="id3913252"></a>env_home</h5>
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<p>Environment home directory, it must exist. Passed to DbEnv::open. </p>
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<h4 class="title"><a id="id3913172"></a>Return Value</h4>
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<p>The opened database environment handle. </p>
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<h4 class="title"><a id="id3913259"></a>See Also</h4>
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<p><a class="link" href="stldbstl_global_functionsregister_db_env.html" title="register_db_env">register_db_env(DbEnv *)</a>
; </p>
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<p><a class="link" href="stldbstl_global_functionsopen_db.html" title="open_db">open_db</a>
; </p>
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<h3 class="title"><a id="id3912943"></a>Class</h3>
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<a class="link" href="dbstl_global_functions.html" title="Chapter 1. Dbstl Global Public Functions">dbstl_global_functions</a>
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