while ( ((n = select(max_fd + 1, &fset, NULL, NULL, NULL)) < 0)
&& (errno == EINTR)); /* wait for data or connection */
if (n < 0) { /* on real error exit */
while ( ((n = select(max_fd + 1, &fset, NULL, NULL, NULL)) < 0)
&& (errno == EINTR)); /* wait for data or connection */
if (n < 0) { /* on real error exit */