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basic_ostream::seekp

Reset position in output stream.

basic_ostream<_Elem, _Tr>& seekp(
     pos_type _Pos
);
basic_ostream<_Elem, _Tr>& seekp(
       off_type _Off,
      ios_base::seekdir _Way
);

Parameters

  • _Pos
    The position in the stream.

  • _Off
    The offset relative to _Way.

  • _Way
    One of the ios_base::seekdir enumerations.

Return Value

A reference to the basic_ostream object.

Remarks

If fail is false, the first member function calls newpos = rdbuf-> pubseekpos(_Pos), for some pos_type temporary object newpos. If fail is false, the second function calls newpos = rdbuf-> pubseekoff(_Off, _Way). In either case, if (off_type)newpos == (off_type)(-1) (the positioning operation fails), then the function calls istr.setstate(failbit). Both functions return *this.

Example

// basic_ostream_seekp.cpp
// compile with: /EHsc
#include <fstream>
#include <iostream>

int main()
{
    using namespace std;
    ofstream x("basic_ostream_seekp.txt");
    streamoff i = x.tellp();
    cout << i << endl;
    x << "testing";
    i = x.tellp();
    cout << i << endl;
    x.seekp(2);   // Put char in third char position in file
    x << " ";

    x.seekp(2, ios::end);   // Put char two after end of file
    x << "z";
}

0
7

Requirements

Header: <ostream>

Namespace: std

See Also

Concepts

basic_ostream Class

basic_ostream Members

iostream Programming

iostreams Conventions