# 15.4. File output¶

Sending output to a file is similar. For example, we could modify the previous program to copy lines from one file to another.

#include <iostream>
using namespace std;

int main () {
ifstream infile ("input-file");
ofstream outfile ("output-file");

if (infile.good() == false || outfile.good() == false) {
cout << "Unable to open one of the files." << endl;
exit (1);
}

while (true) {
getline (infile, line);
if (infile.eof()) break;
outfile << line << endl;
}
}


Create a code block that sends output to a file. First, make sure that both the input file and the output file are able to be opened.