// Reads from STDIN only
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#ifndef BUFFSIZE
#define BUFFSIZE 32768
#endif

int main (int argc, char **argv) {
  int n;
  char buf[BUFFSIZE];

  // Cast to void to silence compiler warnings
  (void)argc;
  (void)argv;

  while ((n = read(STDIN_FILENO, buf, BUFFSIZE)) > 0) {
    if (write(STDOUT_FILENO, buf, n) != n) {
      fprintf(stderr, "Unable to write: %s\n", strerror(errno));
      exit(EXIT_FAILURE);
    }
  }

  if (n < 0) {
    fprintf(stderr, "Unable to read: %s\n", strerror(errno));
    exit(EXIT_FAILURE);
  }

  return EXIT_SUCCESS;
}