Question

I am rather inexperienced C++ programmer, so this question is probably rather basic. I am trying to get the file name for my copula:

string MonteCarloBasketDistribution::fileName(char c)
{
    char result[100];
    sprintf(result, "%c_%s(%s, %s).csv", copula.toString().c_str(), left.toString().c_str(), right.toString().c_str());
    return string(result);
}

which is used in:

MonteCarloBasketDistribution::MonteCarloBasketDistribution(Copula &c, Distribution &l, Distribution &r): copula(c), left(l), right(r)
{
    //.....
    ofstream funit;
    funit.open (fileName('u').c_str());

    ofstream freal;
    freal.open (fileName('r').c_str());
}

However, the files created have rubbish names, consisting mainly from weird characters. Any idea what I am doing wrong and how to fix it?

Answer 1

sprintf has 4 place holders while you give only 3 parameters.

I would suggest:

string MonteCarloBasketDistribution::fileName(char c) {
   std::ostringstream result;
   result << c <<"_"<<copula<<'('<<left<<", "<<right<<").csv";
   return result.str();
}

Your sprintf is not safe for buffer overflow, use rather C99 snprintf or std::stringstream