Cannot open a text file though it is in my resources file

Question

#include <fstream>
#include <iostream>
//Bear in mind that the text file is already in the resources file
int main()
{ 
      ifstream file("Hamlet.txt", ios::in);//open file
      if (file.is_open() == true) cout << "File is open" << endl;
      else if (file.is_open() == false) cout << "File isnt open" << endl;
      return 0;
}

So I'm trying to see if the file is open or not, the text file is in the resources file so as far as I know the path of the file can be written as "Hamlet.txt" . I keep getting File isnt open, what may be the reason? Can anyone bring an explanation to this? Thanks in advance

is the txt file in the directory in which you run the executable (i.e. the working directory)? — Borgleader, Dec 09 '15 at 12:10
http://stackoverflow.com/questions/24097580/ifstreamis-open-vs-ifstreamfail related to checking and you might want to use experimental::filesystem::exists({"Hamlet.txt"}) to check if path exists (or boost::filesystem if you're not on latest msvc). — MojaveWastelander, Dec 09 '15 at 12:22
`ifstream file("Hamlet.txt", ios::in);` will open a file named `Hamlet.txt` that exists in the current working directly (and nothing else). You mention "resources", so what kind of resources are you talking about? — crashmstr, Dec 09 '15 at 13:08

score 2 · Answer 1 · answered Dec 09 '15 at 12:54

If you are talking about Win32 resource files, you can't open your file like that. You need to use the resource API:

HRSRC const rsrc = FindResource(nullptr, MAKEINTRESOURCE(HAMLET), RT_STRING);
HGLOBAL const resource = LoadResource(nullptr, rsrc);
void const* const data = LockResource(resource);
// Use your data here.

HAMLET is a preprocessor macro used to identify your "Hamlet.txt" file from the .rc file.

score 0 · Answer 2 · answered Dec 09 '15 at 12:32

The problem is that you need to run the executable in the same directory where Hamlet.txt lives. This is a big problem in C++, so typically you'll give the absolute path to the file, so you might do something like this:

ifstream file("/path/to/Hamlet.txt", ios::in);

A few other notes: the file is either open, or it's not. Thus, you don't need else if, you can simply use else. Additionally, you can use non-falsey values to indicate true; so you don't need to check == true (though it's more explicit). You could just check if(file.is_open()), which I think is more readable.

Putting these suggestions together, here's what you can do:

#include <fstream>
#include <iostream>

int main()
{ 
      ifstream file("/absolute/path/to/Hamlet.txt", ios::in);
      if (file.is_open()) {
        std::cout << "File is open" << std::endl;
      } else {
        std::cout << "File isnt open" << std::endl;
      }
      return 0;
}

Alternatively, you could check `if(file)`, which checks `std::ios::fail` — erip, Dec 09 '15 at 12:34

Cannot open a text file though it is in my resources file

2 Answers2