typedef struct __db_env DB_ENV;
The DB_ENV object is the handle for a Berkeley DB environment -- a collection including support for some or all of caching, locking, logging and transaction subsystems, as well as databases and log files. Methods off the DB_ENV handle are used to configure the environment as well as to operate on subsystems and databases in the environment.
DB_ENV handles are free-threaded if the DB_THREAD flag is specified to the DB_ENV->open method when the environment is opened. The DB_ENV handle should not be closed while any other handle remains open that is using it as a reference (for example, DB or DB_TXN). Once either the DB_ENV->close or DB_ENV->remove methods are called, the handle may not be accessed again, regardless of the method's return.
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