basic_ostream<charT,traits>& operator<<
(basic_ostream<charT,traits>& (*pf)(basic_ostream<charT,traits>&));
Effects: None. Does not behave as a formatted output function (as described in [ostream.formatted.reqmts]).
basic_ostream<charT,traits>& operator<<
(basic_ios<charT,traits>& (*pf)(basic_ios<charT,traits>&));
Effects: Calls pf(*this). This inserter does not behave as a formatted output function (as described in [ostream.formatted.reqmts]).
basic_ostream<charT,traits>& operator<<
(ios_base& (*pf)(ios_base&));
Effects: Calls pf(*this). This inserter does not behave as a formatted output function (as described in [ostream.formatted.reqmts]).
Returns: *this.
basic_ostream<charT,traits>& operator<<
(basic_streambuf<charT,traits>* sb);
Effects: Behaves as an unformatted output function (as described in [ostream.unformatted], paragraph 1). After the sentry object is constructed, if sb is null calls setstate(badbit) (which may throw ios_base::failure).
Gets characters from sb and inserts them in *this. Characters are read from sb and inserted until any of the following occurs:
end-of-file occurs on the input sequence;
inserting in the output sequence fails (in which case the character to be inserted is not extracted);
an exception occurs while getting a character from sb.
If the function inserts no characters, it calls setstate(failbit) (which may throw ios_base::failure ([iostate.flags])). If an exception was thrown while extracting a character, the function sets failbit in error state, and if failbit is on in exceptions() the caught exception is rethrown.
Returns: *this.
See, for example, the function signature endl(basic_ostream&) ([ostream.manip]).
See, for example, the function signature dec(ios_base&) ([basefield.manip]).