[Dev-C++] Problems with ::tellg()

[Maya <Esc...@ne...>]

I am not sure if the problem below is a bug in GCC 3.2.3 or an error on 
my part, but after reading data from a file I check the file cursor 
position using ::tellg() and tellp() and I get -1; an error in the stream.
---- snip ----
bool data;
fstream f(blabla, blabla)
std::cout << f.tellg() << std::endl; //<--- returns 0
f >> data;
std::cout << f.tellg() << std::endl; //<--- returns -1
-----

The data stored in file 'blabla' is '010101', all bool values.
If I only read the first value in the file (zero) why is tellg() 
reporting a failure in the stream.
A more comprehensive example is at:
http://www.vif.com/users/escalante/IO_BASE_H.html

Can anyone help?
-- 

-- 

Jorge Escalante
FYI
http://www.astro.umd.edu/~marshall/abbrev.html

E-Mail Policy
http://www.vif.com/users/escalante/Email_Policy.html

* You cannot exercise your power to a point of humiliation.
                               - Jean Chretien

* The media's the most powerful entity on earth. They have the 
  power to make the innocent guilty and to make the guilty 
  innocent, and that's power. 
                                - Malcom X
* "Innocent until proven guilty", no... not in Canada!!