std::basic_istream<CharT,Traits>::tellg (3) - Linux Man Pages

std::basic_istream<CharT,Traits>::tellg: std::basic_istream<CharT,Traits>::tellg

NAME

std::basic_istream<CharT,Traits>::tellg - std::basic_istream<CharT,Traits>::tellg

Synopsis


pos_type tellg();


Returns input position indicator of the current associated streambuf object.
Behaves as UnformattedInputFunction, except that gcount() is not affected. After constructing and checking the sentry object, if fail() == true, returns pos_type(-1). Otherwise, returns rdbuf()->pubseekoff(0, std::ios_base::cur, std::ios_base::in).

Parameters


(none)

Return value


The current position of the get pointer on success, pos_type(-1) on failure

Exceptions


failure if an error occurred (the error state flag is not goodbit) and exceptions() is set to throw for that state.
If an internal operation throws an exception, it is caught and badbit is set. If exceptions() is set for badbit, the exception is rethrown.

Example


// Run this code


  #include <iostream>
  #include <string>
  #include <sstream>


  int main()
  {
      std::string str = "Hello, world";
      std::istringstream in(str);
      std::string word;
      in >> word;
      std::cout << "After reading the word \"" << word
                << "\" tellg() returns " << in.tellg() << '\n';
  }

Output:


  After reading the word "Hello," tellg() returns 6

See also


seekoff repositions the file position, using relative addressing
          (virtual protected member function of std::basic_filebuf<CharT,Traits>)
[virtual]


seekoff repositions the next pointer in the input sequence, output sequence, or both, using relative addressing
          (virtual protected member function of std::basic_stringbuf<CharT,Traits,Allocator>)
[virtual]


seekoff repositions the next pointer in the input sequence, output sequence, or both, using relative addressing
          (virtual protected member function of std::strstreambuf)
[virtual]
          sets the input position indicator
seekg (public member function)
          returns the output position indicator
tellp (public member function of std::basic_ostream<CharT,Traits>)
          sets the output position indicator
seekp (public member function of std::basic_ostream<CharT,Traits>)