29 Input/output library [input.output]

29.7 Formatting and manipulators [iostream.format]

29.7.5 Output streams [output.streams]

29.7.5.2 Class template basic_­ostream [ostream]

29.7.5.2.5 Seek members [ostream.seeks]

Each seek member function begins execution by constructing an object of class sentry.
It returns by destroying the sentry object.
pos_type tellp();
Returns: If fail() != false, returns pos_­type(-1) to indicate failure.
Otherwise, returns rdbuf()->​pubseekoff(0, cur, out).
basic_ostream<charT, traits>& seekp(pos_type pos);
Effects: If fail() != true, executes rdbuf()->pubseekpos(pos, ios_­base​::​out).
In case of failure, the function calls setstate(failbit) (which may throw ios_­base​::​failure).
Returns: *this.
basic_ostream<charT, traits>& seekp(off_type off, ios_base::seekdir dir);
Effects: If fail() != true, executes rdbuf()->pubseekoff(off, dir, ios_­base​::​out).
In case of failure, the function calls setstate(failbit) (which may throw ios_­base​::​failure).
Returns: *this.