std::ofstream, check if file exists before writing

I am implementing file saving functionality within a Qt application using C++.

I am looking for a way to check to see if the selected file already exists before writing to it, so that I can prompt a warning to the user.

I am using an std::ofstream and I am not looking for a Boost solution.

File Exists Function

Below is one of my favorite tuck-away functions I keep on hand for multiple uses:

  #include <sys/stat.h>

  /**
    * File Exist Function
    *
    * @desc Check if a file exists
    *
    * @param filename - the name of the file to check
    *
    * @return 'true' if it exist, otherwise returns false.
    * */
    bool fileExists(const std::string& filename){
      struct stat buf;

      if (stat(filename.c_str(), &buf) != -1){ return true; }

      return false;
    }

I find this solution to be much more tasteful than trying to open a file when you don't intend to stream in or out of it.