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< p > Library Version 11.2.5.2< / p >
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< th colspan = "3" align = "center" > open_env< / th >
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< h2 class = "title" style = "clear: both" > < a id = "stldbstl_global_functionsopen_env" > < / a > open_env< / h2 >
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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)
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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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< h5 class = "title" > < a id = "id3593806" > < / 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 = "id3593837" > < / 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 = "id3593844" > < / 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 = "id3593850" > < / 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 = "id3593857" > < / 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 = "id3593862" > < / 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 = "id3593781" > < / a > Return Value< / h4 >
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< p > The opened database environment handle. < / p >
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< h4 class = "title" > < a id = "id3593868" > < / 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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