protected member function
void swap (basic_ios& x) noexcept;
Exchanges all internal members between x and
*this, except the pointers to the associated stream buffers: rdbuf shall return the same in both objects as before the call.
Derived classes can call this function to implement custom swap functions.
- Another stream object of the same type.
Modifies both stream objects (
*this and x).
No-throw guarantee: this member function never throws exceptions.