#include <db.h> int DB_ENV->set_encrypt(DB_ENV *dbenv, const char *passwd, u_int32_t flags);
Set the password used by the Berkeley DB library to perform encryption and decryption.
         The DB_ENV->set_encrypt() method configures a database environment,
         not only operations performed using the specified 
         DB_ENV  handle.
    
         The DB_ENV->set_encrypt() method may not be called after the 
         DB_ENV->open()  method is called.
         If the database environment already exists when 
         DB_ENV->open()  is called, the
         information specified to DB_ENV->set_encrypt() must be consistent
         with the existing environment or an error will be returned.
    
         The DB_ENV->set_encrypt() 
            
                  method returns a non-zero error value on failure and 0 on success.
            
            
        
    
                         The DB_ENV->set_encrypt() 
            
                 method may fail and return one of the following non-zero errors:
            
            
        
                    
If the method was called after DB_ENV->open() was called; or if an invalid flag value or parameter was specified.