std::ostrstream::rdbuf
| strstreambuf* rdbuf() const; | 
Returns a pointer to the associated std::strstreambuf, casting away its constness (despite the const qualifier on the member function).
Parameters
(none).
Return value
Pointer to the associated std::strsteambuf, with constness cast away.
Example
#include <strstream>
int main()
{
    const std::ostrstream buf;
    std::strstreambuf* ptr = buf.rdbuf();
}
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