char* str();
Returns a pointer to the object's internal character array. If the strstreambuf object was constructed with a user-supplied buffer, then that buffer address is returned. If the object has a dynamic array, then str freezes the array. You must not send characters to a frozen strstreambuf object, and you are responsible for deleting the array. If a dynamic array is empty, then str returns NULL.
You can use the freeze function with a 0 parameter to unfreeze a frozen strstreambuf object.