tests ios modes when file doesn't exist; which ones will create file

ios modes.cpp

#include <fstream>
#include <iostream>

using namespace std;

void test(ios_base::openmode bits, char* name) {
    fstream f;
    f.open(name, bits);
    cout << "Tried " << name;
    if(f.is_open()) {
        cout << " and was successful." << endl;
        f.close();
    } else {
        cout << " and failed." << endl;
    }
}
int main(void) {
    ios_base::openmode m = ios_base::out;
    test(m, "out");
    test(m | ios_base::trunc, "out trunc");
    test(m | ios_base::app, "out app");
    test(m | ios_base::ate, "out ate");
    m = ios_base::in;
    test(m, "in");
    test(m | ios_base::trunc, "in trunc");
    test(m | ios_base::app, "in app");
    test(m | ios_base::ate, "in ate");
    m = ios_base::in | ios_base::out;
    test(m, "inout");
    test(m | ios_base::trunc, "inout trunc");
    test(m | ios_base::app, "inout app");
    test(m | ios_base::ate, "inout ate");
    return 0;
}