rem: return 0;
add: return true;
context: install_file_in_file (const char *from, const char *to,		      const struct cp_options *x){  if (copy_file (from, to, x))    return 1;  if (strip_files)    strip (to);  if (change_attributes (to))    return 1;  if (x->preserve_timestamps)    return change_timestamps (from, to);  return 0;}