ostream::tellp - C++ Reference

ostream::tellp

public member function

streampos tellp ( );

Get position of put pointer

Returns the absolute position of the put pointer.

The put pointer determines the location in the output sequence where the next output operation is going to take place.

Parameters

none

Return Value

An integral value of type streampos with the number of characters between the beginning of the output sequence and the current position.

Failure is indicated by returning a value of -1.

Example

// position of put pointer
#include <fstream>
using namespace std;

int main () {
  long pos;

  ofstream outfile;
  outfile.open ("test.txt");

  outfile.write ("This is an apple",16);
  pos=outfile.tellp();
  outfile.seekp (pos-7);
  outfile.write (" sam",4);

  outfile.close();

  return 0;
}

In this example, tellp is used to get the position of the put pointer after the writing operation. The pointer is then moved back 7 characters to modify the file at that position, so the final content of the file shall be:
This is a sample

Basic template member declaration

(basic_ostream<charT,traits>)

typedef traits::pos_type pos_type;
pos_type tellp ();

Parameters

Return Value

Example

Basic template member declaration

See also