1*27700Smckusick .\" Copyright (c) 1986 Regents of the University of California.
2*27700Smckusick .\" All rights reserved.  The Berkeley software License Agreement
3*27700Smckusick .\" specifies the terms and conditions for redistribution.
4*27700Smckusick .\"
5*27700Smckusick .\"	@(#)strchkread.c	6.1 (Berkeley) 05/04/86
6*27700Smckusick .\"
7*27700Smckusick #include <sys/types.h>
8*27700Smckusick #include <sys/socket.h>
9*27700Smckusick #include <netinet/in.h>
10*27700Smckusick #include <netdb.h>
11*27700Smckusick #include <stdio.h>
12*27700Smckusick #define TRUE 1
13*27700Smckusick 
14*27700Smckusick /*
15*27700Smckusick  * This program uses select() to check that someone is trying to connect
16*27700Smckusick  * before calling accept().
17*27700Smckusick  */
18*27700Smckusick 
19*27700Smckusick main()
20*27700Smckusick {
21*27700Smckusick 	int             sock, length;
22*27700Smckusick 	struct sockaddr_in server;
23*27700Smckusick 	int             msgsock;
24*27700Smckusick 	char            buf[1024];
25*27700Smckusick 	int             rval;
26*27700Smckusick 	int             i;
27*27700Smckusick 	int             ready;
28*27700Smckusick 	struct timeval  to;
29*27700Smckusick 
30*27700Smckusick 	/* Create socket */
31*27700Smckusick 	sock = socket(AF_INET, SOCK_STREAM, 0);
32*27700Smckusick 	if (sock < 0) {
33*27700Smckusick 		perror("opening stream socket");
34*27700Smckusick 		exit(0);
35*27700Smckusick 	}
36*27700Smckusick 	/* Name socket using wildcards */
37*27700Smckusick 	server.sin_family = AF_INET;
38*27700Smckusick 	server.sin_addr.s_addr = INADDR_ANY;
39*27700Smckusick 	server.sin_port = 0;
40*27700Smckusick 	if (bind(sock, &server, sizeof(server))) {
41*27700Smckusick 		perror("binding stream socket");
42*27700Smckusick 	}
43*27700Smckusick 	/* Find out assigned port number and print it out */
44*27700Smckusick 	length = sizeof(server);
45*27700Smckusick 	if (getsockname(sock, &server, &length)) {
46*27700Smckusick 		perror("getting socket name");
47*27700Smckusick 		exit(0);
48*27700Smckusick 	}
49*27700Smckusick 	printf("Socket has port #%d\en", ntohs(server.sin_port));
50*27700Smckusick 
51*27700Smckusick 	/* Start accepting connections */
52*27700Smckusick 	listen(sock, 5);
53*27700Smckusick 	do {
54*27700Smckusick 		ready = 1 << sock;
55*27700Smckusick 		to.tv_sec = 5;
56*27700Smckusick 		select(20, &ready, 0, 0, &to);
57*27700Smckusick 		if (ready) {
58*27700Smckusick 			msgsock = accept(sock, 0, 0);
59*27700Smckusick 			do {
60*27700Smckusick 				for (i = 0; i < 1024; i++)
61*27700Smckusick 					buf[i] = '\e0';
62*27700Smckusick 				if ((rval = read(msgsock, buf, 1024)) < 0)
63*27700Smckusick 					perror("reading stream message");
64*27700Smckusick 				i = 0;
65*27700Smckusick 				if (rval == 0)
66*27700Smckusick 					printf("Ending connection\en");
67*27700Smckusick 				else
68*27700Smckusick 					printf("-->%s\en", buf);
69*27700Smckusick 			} while (rval != 0);
70*27700Smckusick 			close(msgsock);
71*27700Smckusick 		} else
72*27700Smckusick 			printf("Do something else\en");
73*27700Smckusick 	} while (TRUE);
74*27700Smckusick }
75