> mInputStream variable is an ifstream
> the text gets read into the program correctly, but the content is erased from the file
If you mean the `physical' file, then it can't happen. You don't have writing permission.
If you mean that you can't do readInputFile() several times, I suppose that the get pointer went to the end of the file.
Reading should not change the file. Are you sure that is what happens?
When opening a file with ofstream it will remove the old content of the file. Maybe this is what happens. If you want to keep the old content you should pass the ate or the app flag when you open the file for writing. mOutputStream.open(mOutputSRC.c_str(), std::ios::ate);