Can we set a NSString from objC in UITextView to store value from textview.text

Is there any way we can set a NSString from objC in UITextView by extending or without extending UITextView(without extending preferably). Reason -: My logic for action on text change will be triggered from cpp code .That is why i need to send the textview.text to objC on change of character .Is it possible to have a buffer of such type ? ,and if yes, is the memory delocation and allocation of buffer managed by xcode ? If any of the above thing is not possible ,then is there anyother way to achive similar behavior ? Any answer can help.