#include <db.h>
 
DB_ENV->get_backup_callbacks(DB_ENV, 
        int (**open_func)(DB_ENV *, const char *dbname, 
                          const char *target, void **handle),
        int (**write_func)(DB_ENV *, u_int32_t offset_gbytes, 
                           u_int32_t offset_bytes, u_int32_t size, 
                           u_int8_t *buf, void *handle),
        int (**close_func)(DB_ENV *, const char *dbname, void *handle));  

The DB_ENV->get_backup_callbacks() method retrieves the three callback functions which can be used by the DB_ENV->backup() or DB_ENV->dbbackup() methods to override their default behavior. These callbacks are configured using the DB_ENV->set_backup_callbacks() method.

The DB_ENV->get_backup_callbacks() method may be called at any time during the life of the application.

The DB_ENV->get_backup_callbacks() method returns a non-zero error value on failure and 0 on success.