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open_env
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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
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Function Details</h3>
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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>
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<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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Parameters</h4>
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<h5 class="title"><a id="id1542999"></a>
oflags </h5>
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<p>Environment open flags, passed to DbEnv::open. </p>
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set_flags </h5>
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<p>Flags to set to the created environment before opening it. </p>
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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="id1542303"></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="id1543261"></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="id1541001"></a>
env_home </h5>
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<p>Environment home directory, it must exist. Passed to DbEnv::open. </p>
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Return Value</h4>
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<p>The opened database environment handle. </p>
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See Also</h4>
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<p>
</p>
<p><a class="link" href="stldbstl_global_functionsregister_db_env.html" title="register_db_env">register_db_env(DbEnv *)</a>
; </p>
<p><a class="link" href="stldbstl_global_functionsopen_db.html" title="open_db">open_db</a>
; </p>
<p> </p>
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Class</h3>
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dbstl_global_functions</a>
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