#include <netinet/in.h>
#include <sys/socket.h>
#include <sys/types.h>

/**
 * getClientSocket() listens on the specified port, and returns
 *   a socket connected to the first client that contacts us.
 */
int getClientSocket(int port)
{
  /* Note: This code performs NO error checking.  A sane version  */
  /*  would carefully check the proper return values from each of */
  /*  the library calls.                                          */

  int listenSocket = -1;
  int clientSocket = -1;
  int size = 0;

  struct sockaddr_in serverAddress, freshSocketAddress;

  // Create a socket.
  listenSocket = socket(AF_INET,SOCK_STREAM,0);

  // Zero out Internet Socket struct
  memset((char*)&serverAddress, 0,
		sizeof(struct sockaddr_in));

  serverAddress.sin_family = AF_INET;
  serverAddress.sin_addr.s_addr=htonl(INADDR_ANY);
  // INADDR_ANY interpreted as use MY address.
  serverAddress.sin_port=htons(port);

  // Bind socket to port on this machine.
  bind(listenSocket,
       (struct sockaddr *)&serverAddress,
       sizeof(struct sockaddr));

  // Setup socket to listen for connections.
  listen(listenSocket,1);

  // Wait for client, then give me new socket for
  //  the connection with that client.
  clientSocket = accept(listenSocket,
	       (struct sockaddr*)&freshSocketAddress,
	       &size);

  // Tidyness is a virtue.
  close(listenSocket);

  return clientSocket;
}
  // read() and write() or send() and recv() with
  // clientSocket file descriptor.