rem: tac_file (const char *file)
add: tac_file (const char *filename)
context: tac_file (const char *file){  int errors;  FILE *in;  in = fopen (file, "r");  if (in == NULL)    {      error (0, errno, "%s", file);      return 1;    }  SET_BINARY (fileno (in));  errors = tac_seekable (fileno (in), file);  if (ferror (in) || fclose (in) == EOF)    {      error (0, errno, "%s", file);      return 1;    }  return errors;}