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c++argumentsifstream

Why is my file is not opening with ifstream C++?


Though this is a fairly simple question, I am having trouble opening the file through the inputFileStream(inputFilePath). Could someone just lead me in the correct direction (I'm not here to be given answers for a school assignment)?

#include <cmath>
#include <fstream>
#include <iomanip>
#include <iostream>
#include <sstream>

using namespace std;

const string ID_LINE = "James McMillan - CS 1336 050 - Assignment 26";

int main(int argc, char *argv[]) {
    cout << ID_LINE << endl << endl;

    // guard clause - invalid number of arguments
    if (argc != 3) {
        cout << "Usage: " << argv[0] << "<input file path> <output file path>" << endl;
        return 1;
    }

    //extract arguments
    string programPath = argv[0];
    string inputFilePath = argv[1];
    string outputFilePath = argv[2];

    cout << "Program path: " << programPath << endl;
    cout << "Input file path: " << inputFilePath << endl;
    cout << "Output file path: " << outputFilePath << endl << endl;


    cout << "Creating input file stream..." << endl;
    ifstream inputFileStream;
    cout << "Created input file stream." << endl;

    cout << "Opening input file stream: " << inputFilePath << endl;
    inputFileStream.open(inputFilePath);

    if (!inputFileStream.is_open()) {
        cout << "Unable to open input file stream: " << inputFilePath << endl;
        return 1;
    }
}

Solution

  • Your solution might come from checking if the file exists, try

    //Add this at the top
    #include <experimental/filesystem>
    //somewhere in the body
    const auto has_the_file = std::experimental::filesystem::exists(inputFilePath);
    if (!has_the_file)
    {
        std::cout << "Oh No! Can't find" << inputFilePath << std::endl;
    }
    

    Also instead of parsing the arguments, I would manually set the paths to confirm your expectations on how to specify file paths.