#include <sys/types.h>
#include <sys/socket.h>
#include <stdio.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/un.h>
#include <unistd.h>

int main () {
	int server_sockfd, client_sockfd;
	int server_len, client_len;
	struct sockaddr_in server_address;
	struct sockaddr_in client_address;
	
	server_sockfd = socket (AF_INET, SOCK_STREAM, 0);
	server_address.sin_family = AF_INET;
	server_address.sin_addr.s_addr = inet_addr ("127.0.0.1");
	server_address.sin_port = 9734;
	server_len = sizeof (server_address);
	bind (server_sockfd, (struct sockaddr *)&server_address, server_len);
	
	listen (server_sockfd, 5);
	while (1) {
		char ch;
		
		printf ("server waiting\n");
		
		client_sockfd = accept (server_sockfd, (struct sockaddr *)&client_address, &client_len);
		
		read (client_sockfd, &ch, 1);
		ch++;
		write (client_sockfd, &ch, 1);
		close (client_sockfd);
	}
}