title: Portable way to get file size in C/C++
body: <p>I need to determin the byte size of a file. </p>
  
  <p>The coding language is C++ and the code should work with Linux, windows and any other operating system. This implies using standard C or C++ functions/classes.</p>
  
  <p>This trivial need has apparently no trivial solution.  </p>