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 of 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 created using the db_env_create
            method, and 
        
        are opened using the DB_ENV->open()
        method.
    
When you are done using your environment, close it using the DB_ENV->close() method. Before closing your environment, make sure all open database handles are closed first. See the DB->close() method for more information.
| Database Environment Operations | Description | 
|---|---|
| DB_ENV->backup() | Hot back up an entire environment | 
| DB_ENV->close() | Close an environment | 
| db_env_create | Create an environment handle | 
| DB_ENV->dbbackup() | Hot back up a single environment file | 
| DB_ENV->dbremove() | Remove a database | 
| DB_ENV->dbrename() | Rename a database | 
| DB_ENV->err() | Error message | 
| DB_ENV->failchk() | Check for thread failure | 
| DB_ENV->fileid_reset() | Reset database file IDs | 
| db_full_version | Return full version information | 
| DB->get_env() | Return the DB's underlying DB_ENV handle | 
| DB_ENV->get_home() | Return environment's home directory | 
| DB_ENV->get_open_flags() | Return flags with which the environment was opened | 
| DB_ENV->log_verify() | Verify log files of an environment. | 
| DB_ENV->lsn_reset() | Reset database file LSNs | 
| DB_ENV->open() | Open an environment | 
| DB_ENV->remove() | Remove an environment | 
| DB_ENV->stat_print() | Environment statistics | 
| db_strerror | Error strings | 
| db_version | Return version information | 
| Environment Configuration | |
| DB_ENV->add_data_dir() | Add an environment data directory | 
| DB_ENV->set_alloc() | Set local space allocation functions | 
| DB_ENV->set_app_dispatch() | Configure application recovery callback | 
| DB_ENV->set_backup_callbacks(), DB_ENV->get_backup_callbacks() | Set/get callbacks used for environment hot backups | 
| DB_ENV->set_backup_config(), DB_ENV->get_backup_config() | Set/get environment hot backup configuration options | 
| DB_ENV->set_data_dir(), DB_ENV->get_data_dirs() | Set/get the environment data directory | 
| DB_ENV->set_data_len(), DB_ENV->get_data_len() | Set/get the command line utility byte limit | 
| DB_ENV->set_create_dir(), DB_ENV->get_create_dir() | Add an environment data directory | 
| DB_ENV->set_encrypt(), DB_ENV->get_encrypt_flags() | Set/get the environment cryptographic key | 
| DB_ENV->set_event_notify() | Set event notification callback | 
| DB_ENV->set_errcall() | Set error message callbacks | 
| DB_ENV->set_errfile(), DB_ENV->get_errfile() | Set/get error message FILE | 
| DB_ENV->set_errpfx(), DB_ENV->get_errpfx() | Set/get error message prefix | 
| DB_ENV->set_feedback() | Set feedback callback | 
| DB_ENV->set_flags(), DB_ENV->get_flags() | Environment configuration | 
| DB_ENV->set_intermediate_dir_mode(), DB_ENV->get_intermediate_dir_mode() | Set/get intermediate directory creation mode | 
| DB_ENV->set_isalive() | Set thread is-alive callback | 
| DB_ENV->set_memory_init(), DB_ENV->get_memory_init() | Set/get initial memory allocation | 
| DB_ENV->set_memory_max(), DB_ENV->get_memory_max() | Set/get maximum memory allocation | 
| DB_ENV->set_metadata_dir(), DB_ENV->get_metadata_dir() | Set/get the directory containing environment metadata | 
| DB_ENV->set_msgcall() | Set informational message callback | 
| DB_ENV->set_msgfile(), DB_ENV->get_msgfile() | Set/get informational message FILE | 
| DB_ENV->set_shm_key(), DB_ENV->get_shm_key() | Set/get system memory shared segment ID | 
| DB_ENV->set_thread_count(), DB_ENV->get_thread_count() | Set/get approximate thread count | 
| DB_ENV->set_thread_id() | Set thread of control ID function | 
| DB_ENV->set_thread_id_string() | Set thread of control ID format function | 
| DB_ENV->set_timeout(), DB_ENV->get_timeout() | Set/get lock and transaction timeout | 
| DB_ENV->set_tmp_dir(), DB_ENV->get_tmp_dir() | Set/get the environment temporary file directory | 
| DB_ENV->set_verbose(), DB_ENV->get_verbose() | Set/get verbose messages | 
| DB_ENV->set_cachesize(), DB_ENV->get_cachesize() | Set/get the environment cache size |