Accessing file larger than 2Go

[Pierre Lindenbaum]

Hello, I'm trying to read a file that is larger than 2G owith an ifstream
but  its fails and I have strerror(errno)==EOVERFLOW

                ifstream in;
                errno=0;
                in.open(fname,ios::in);
                if(in.is_open()==false)
                        {
                        cerr << "Can't open \"" << fname << "\"";
                        if(errno!=0)
                                {
                                cerr << strerror(errno);
                                }
                        cerr << endl;
                        continue;
                        }
                stuff(in);
                in.close();


Under solaris, how can I compile my program with g++ in order it handles
large files ?
Thank you in advance !

        Pierre