// cc -o server server.c
#include <stdio.h>
#include <string.h>
#include <arpa/inet.h>
#include <unistd.h>


int main(void) {

	int listen_sock, server_sock;
	struct sockaddr_in sa, nsa;
	socklen_t nlen;
	int ch;

	listen_sock = socket(AF_INET, SOCK_STREAM, 0);
	sa.sin_family = AF_INET;
	sa.sin_port = 26000;
	sa.sin_addr.s_addr = INADDR_ANY;
	bind(listen_sock, (struct sockaddr *)&sa, sizeof(sa));
	listen(listen_sock, 5);
	printf("Listening...\n");

	nlen = sizeof(nsa);
	server_sock = accept(listen_sock, (struct sockaddr *)&nsa, &nlen);
	printf("Connected.\nReceiving characters.\n");

	while (1) {
		read(server_sock, &ch, sizeof(ch));
		printf("%c", ch);  fflush(stdout);
		if (ch == '!')
			break;
		write(server_sock, &ch, sizeof(ch));
	}

	close(server_sock);
	close(listen_sock);
	
	return 0;

}