#include <db_cxx.h> int Db::set_encrypt(const char *passwd, u_int32_t flags);
Set the password used by the Berkeley DB library to perform encryption and decryption.
Because databases opened within Berkeley DB environments use the password specified to the environment, it is an error to attempt to set a password in a database created within an environment.
             The Db::set_encrypt() method may not be called after the 
             Db::open()  method is called.
    
         The Db::set_encrypt() 
            
            
                method either returns a non-zero error value or throws an
                exception that encapsulates a non-zero error value on
                failure, and returns 0 on success.
            
        
    
                         The Db::set_encrypt() 
            
            
                method may fail and throw a DbException 
                exception, encapsulating one of the following non-zero errors, or return one
                of the following non-zero errors:
            
        
                    
If the method was called after Db::open() was called; or if an invalid flag value or parameter was specified.