gistfile1.cpp

#include <iostream>
#include <cstdio>

using namespace std;

#define CONCAT(a, b) a##b

#define file_type CONCAT(FI, LE)
#define file_open CONCAT(fo, pen)
#define file_scanf CONCAT(fs, canf)
#define file_printf CONCAT(fp, rintf)
#define file_close CONCAT(fc, lose)

int main(int argc, const char *argv[]) {
  file_type * f = file_open("use_macro_to_create_file", "w");
  file_printf(f, "https://gist.github.com/chengluyu/6202958");
  file_close(f);
  return 0;
}