If s is a null pointer and n is zero, this function has no effect.
Otherwise, the effect is implementation-defined: some implementations do nothing, while some implementations clear the std::string member currently used as the buffer and begin using the user-supplied character array of size n, whose first element is pointed to by s, as the buffer and the input/output character sequence.
This function is protected virtual, it may only be called through
pubsetbuf() or from member functions of a user-defined class derived from
|s||-||pointer to the first CharT in the user-provided buffer or null|
|n||-||the number of CharT elements in the user-provided buffer or zero|
 Return value
Test for the stringstream's setbuf functionality.
3.14 (on GNU g++/libstdc++ and SunPro C++/roguewave) <nothing> (on MS Visual Studio 2010, SunPro C++/stlport4, CLang++/libc++)
 See also
| invokes setbuf() |
(public member function of