E_NOTICE error if the salt
     parameter is omitted.
    
   0
     for its length parameter.
    
   @file syntax are now only supported
     if the CURLOPT_SAFE_UPLOAD option is set to
     false. CURLFile should be used instead.
    
   source parameter of
     mcrypt_create_iv() now defaults to
     MCRYPT_DEV_URANDOM instead of
     MCRYPT_DEV_RANDOM.
    
   crypto_type parameter to be optional if the
     stream's SSL context includes the new crypto_type
     option.
    
   null if
     the attribute could not be found, like
     XMLReader::getAttribute().
    
   