explicit basic_stringbuf(ios_base::openmode which =
ios_base::in | ios_base::out);
Effects: Constructs an object of class basic_stringbuf, initializing the base class with basic_streambuf() ([streambuf.cons]), and initializing mode with which.
Postcondition: str() == "".
explicit basic_stringbuf(const basic_string<charT,traits,Allocator>& s,
ios_base::openmode which = ios_base::in | ios_base::out);
Effects: Constructs an object of class basic_stringbuf, initializing the base class with basic_streambuf() ([streambuf.cons]), and initializing mode with which. Then calls str(s).
basic_stringbuf(basic_stringbuf&& rhs);
Effects: Move constructs from the rvalue rhs. It is implementation-defined whether the sequence pointers in *this (eback(), gptr(), egptr(), pbase(), pptr(), epptr()) obtain the values which rhs had. Whether they do or not, *this and rhs reference separate buffers (if any at all) after the construction. The openmode, locale and any other state of rhs is also copied.
Postconditions: Let rhs_p refer to the state of rhs just prior to this construction and let rhs_a refer to the state of rhs just after this construction.
str() == rhs_p.str()
gptr() - eback() == rhs_p.gptr() - rhs_p.eback()
egptr() - eback() == rhs_p.egptr() - rhs_p.eback()
pptr() - pbase() == rhs_p.pptr() - rhs_p.pbase()
epptr() - pbase() == rhs_p.epptr() - rhs_p.pbase()
if (eback()) eback() != rhs_a.eback()
if (gptr()) gptr() != rhs_a.gptr()
if (egptr()) egptr() != rhs_a.egptr()
if (pbase()) pbase() != rhs_a.pbase()
if (pptr()) pptr() != rhs_a.pptr()
if (epptr()) epptr() != rhs_a.epptr()