#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <fstream>
#include <iostream>

#include <string>

using namespace std;

const size_t BUF_SIZE {1024};

void Usage(string progname);

int main( int argc, char * argv[]) {

   int flags;
   int inFD{STDIN_FILENO} , outFD{STDOUT_FILENO};
   mode_t mode;

   if (argc != 3) {
      Usage(argv[0]);
      exit(0);
   }

   string inFileName{argv[1]};
   string outFileName{argv[2]};


   if (inFileName != "-") {
      close(STDIN_FILENO);
      inFD =  open(inFileName.c_str(), O_RDONLY);
   }

   if (outFileName != "-") {

       close(STDOUT_FILENO);

       flags = O_WRONLY | O_TRUNC | O_CREAT;
       mode = S_IRUSR | S_IWUSR | S_IROTH | S_IRGRP;

      outFD = open(outFileName.c_str(),flags, mode);
   } 

/*
   ssize_t numRead;
   char BUFFER[BUF_SIZE];

   while((numRead = read(inFD, BUFFER, BUF_SIZE)) > 0) {
       write(outFD, BUFFER, numRead);
   }

*/

   char c = cin.get();
   while (cin) {
      cout << c;
      c = cin.get();
   }

   close(inFD);
   close(outFD);

   return 0;
}

void Usage(string progname){
  cerr << "Usage: " << progname << " infile outfile" << endl;
  cerr << "\tInfile or outfile can be - for stdin/stdout" << endl;
  cerr << endl;
}