#include <unistd.h>
#include <fcntl.h>
#include <error.h>
#include <errno.h>

int main(int argc, char *argv[])
{
   int in;
   if (argc < 2)
      error(1, 0, "Usage: %s File", argv[0]);
   in = open(argv[1],O_RDONLY);
   if (in < 0)
      error(errno, errno, "Can't open %s", argv[1]);
   close(in);
   return 0;
}