#include <db.h> int DB_ENV->get_lg_dir(DB_ENV *dbenv, const char **dirp);
            The DB_ENV->get_lg_dir() method returns the log directory, which is the location for
            logging files. You can manage this value using the
            DB_ENV->set_lg_dir()
            method. 
    
         The DB_ENV->get_lg_dir() method may be called at any time during the
         life of the application.
    
         The DB_ENV->get_lg_dir() 
            
                  method returns a non-zero error value on failure and 0 on success.