#include <netinet/in.h>
#include <err.h>
#include <stdio.h>
#include <unistd.h>

int
main(void)
{
  struct sockaddr_in laddr=
    {.sin_family=AF_INET, .sin_port=htons(5001), .sin_addr={INADDR_ANY}};
  struct sockaddr_storage addr;
  int skt,alen=sizeof(addr);
  fd_set r,w,e;
  struct timeval to;

  if (-1==(skt=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP)))err(1,"opening");
  if (-1==bind(skt,(struct sockaddr*)&laddr,sizeof(laddr)))err(1,"bind");
  fprintf(stderr,"Listening....\n");
  if (-1==listen(skt,1))err(1,"listen");
  switch(fork()){
  case -1: err(1,"fork");
  case 0:
    sleep(1); // Ensure parent wins the race.
    fprintf(stderr,"closing...\n");
    close(skt); // block here until parent returns from select()
    fprintf(stderr,"closed\n");
    return 0;
  default:
    FD_ZERO(&r);
    FD_ZERO(&w);
    FD_ZERO(&e);
    to.tv_sec=10;
    to.tv_usec=0;
    FD_SET(skt,&r);
    fprintf(stderr,"selecting...\n");
    if(-1==(s=select(skt+1,&r,&w,&e,&to)))err(1,"select");
    fprintf(stderr,"selected\n");
    }
  }
  return 0;
}