Don't know that this will help...
Guess you'll have to look deeper into CFile and/or CString
Code
#include <iostream>
#include <fstream>
using namespace std;
int main () {
fstream filestr;
string delim = "\t", quotes = "\"", content;
filestr.open ("test.txt", fstream::in | fstream::out | fstream::app);
content = quotes + "1,23456789" + quotes + delim;
content += quotes + "9,12345678" + quotes + delim;
filestr << content;
filestr.close();
return 0;
}
Output
"1,23456789" "9,12345678"