AF_INET sockets, code examples needed.

[Jordan K. Hubbard]

Thank you for all the responses on my AF_UNIX domain socket
question. selecting the accepting socket works nicely.

Now for another question, I've built a simplistic server/client model
for testing AF_INET sockets and it doesn't work.. I've declared the
server as a 'service' and done the appropriate get host and server
calls and bound the socket. Connections are accepted, but the accept
call returns a fd with a value of zero!

This causes obvious problems when the server tries to read the
new socket..

The salient portions of the client/server code follow.

-- client code --
(host name is passed as 'host')

	struct	hostent *cafe;	/* host table entry */
	struct	servent *waiter;	/* sevice file entry */
	struct	sockaddr_in sin;/* socket address */

	if ((cafe = gethostbyname(host)) == NULL) {
		fprintf(stderr, "client: Unknown host %s\n", host);
		return(-1);
	}

	if ((waiter = getservbyname("george", "tcp")) == NULL) {
		fprintf(stderr, "client: george/tcp: unknown service\n");
		return(-1);
	}

	if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
		perror("client");
		return(-1);
	}

	sin.sin_family = cafe->h_addrtype;      
	bcopy(cafe->h_addr, (caddr_t)&sin.sin_addr, cafe->h_length);
	sin.sin_port = waiter->s_port;

	if (connect(fd, (caddr_t)&sin, sizeof(sin), 0) < 0) {
		perror("client");
		close(fd);
		return(-1);
	}

	/* Send a silly message to the server */
	strcpy(buff, "a burger and fries");
	write(fd, buff, strlen(buff)); 

	/* read in the response */
		while (read(fd, buff, 80) > 0)
			printf("Waiter: '%s'\n", buff);
		close(fd);

-- server code --

	struct	servent *me;	/* sevice file entry */
	struct	sockaddr_in sin;/* socket address */
	int	fd;
	int nf,	sz;				/* new fd and size of sin */
	char buff[132], buff2[132];			/* server buffer */

	if ((sir = getservbyname("george", "tcp")) == NULL) {
		fprintf(stderr, "server: george/tcp: unknown service\n");
		return(-1);
	}

	if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
		perror("server (socket):");
		return(-1);
	}

    sin.sin_family = AF_INET;
    sin.sin_port = sir->s_port;
	sz = sizeof(sin);
	if (bind(fd, (caddr_t)&sin, sz) < 0) {
		perror("server/bind");
		return(-1);
	}

	if (listen(fd, 5) < 0) {
		perror("server/listen");
		return(-1);
	}
	/* deal with requests */
	while (are_open) {
		if (nf = accept(fd, (caddr_t)&sin, &sz) < 0) {  THIS IS THE PUD
			perror("server/accept");
			return(-1);
		}
		while (read(nf, buff, 132)) {
			if (!strcmp(buff, "health inspection")) {
				are_open = FALSE;
				break;
			}
			sprintf(buff2, "%s, coming right up sir.\n", buff);
			write(nf, buff2, 132);
		}
		close(nf);
	}
-- 
			Jordan K. Hubbard
			@ Genstar Rental Electronics.
			Palo Alto, CA.
			{pesnta, decwrl, dual, pyramid}!greipa!jordan

			"Ack ack!".

				- William the feline