xref: /netbsd/share/doc/psd/20.ipctut/streamread.c (revision bf9ec67e)
1 .\"	$NetBSD: streamread.c,v 1.2 1998/01/09 06:55:04 perry Exp $
2 .\"
3 .\" Copyright (c) 1986, 1993
4 .\"	The Regents of the University of California.  All rights reserved.
5 .\"
6 .\" Redistribution and use in source and binary forms, with or without
7 .\" modification, are permitted provided that the following conditions
8 .\" are met:
9 .\" 1. Redistributions of source code must retain the above copyright
10 .\"    notice, this list of conditions and the following disclaimer.
11 .\" 2. Redistributions in binary form must reproduce the above copyright
12 .\"    notice, this list of conditions and the following disclaimer in the
13 .\"    documentation and/or other materials provided with the distribution.
14 .\" 3. All advertising materials mentioning features or use of this software
15 .\"    must display the following acknowledgement:
16 .\"	This product includes software developed by the University of
17 .\"	California, Berkeley and its contributors.
18 .\" 4. Neither the name of the University nor the names of its contributors
19 .\"    may be used to endorse or promote products derived from this software
20 .\"    without specific prior written permission.
21 .\"
22 .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 .\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 .\" SUCH DAMAGE.
33 .\"
34 .\"	@(#)streamread.c	8.1 (Berkeley) 6/8/93
35 .\"
36 #include <sys/types.h>
37 #include <sys/socket.h>
38 #include <netinet/in.h>
39 #include <netdb.h>
40 #include <stdio.h>
41 #define TRUE 1
42 
43 /*
44  * This program creates a socket and then begins an infinite loop. Each time
45  * through the loop it accepts a connection and prints out messages from it.
46  * When the connection breaks, or a termination message comes through, the
47  * program accepts a new connection.
48  */
49 
50 main()
51 {
52 	int sock, length;
53 	struct sockaddr_in server;
54 	int msgsock;
55 	char buf[1024];
56 	int rval;
57 	int i;
58 
59 	/* Create socket */
60 	sock = socket(AF_INET, SOCK_STREAM, 0);
61 	if (sock < 0) {
62 		perror("opening stream socket");
63 		exit(1);
64 	}
65 	/* Name socket using wildcards */
66 	server.sin_family = AF_INET;
67 	server.sin_addr.s_addr = INADDR_ANY;
68 	server.sin_port = 0;
69 	if (bind(sock, &server, sizeof(server))) {
70 		perror("binding stream socket");
71 		exit(1);
72 	}
73 	/* Find out assigned port number and print it out */
74 	length = sizeof(server);
75 	if (getsockname(sock, &server, &length)) {
76 		perror("getting socket name");
77 		exit(1);
78 	}
79 	printf("Socket has port #%d\en", ntohs(server.sin_port));
80 
81 	/* Start accepting connections */
82 	listen(sock, 5);
83 	do {
84 		msgsock = accept(sock, 0, 0);
85 		if (msgsock == -1)
86 			perror("accept");
87 		else do {
88 			bzero(buf, sizeof(buf));
89 			if ((rval = read(msgsock, buf, 1024)) < 0)
90 				perror("reading stream message");
91 			i = 0;
92 			if (rval == 0)
93 				printf("Ending connection\en");
94 			else
95 				printf("-->%s\en", buf);
96 		} while (rval != 0);
97 		close(msgsock);
98 	} while (TRUE);
99 	/*
100 	 * Since this program has an infinite loop, the socket "sock" is
101 	 * never explicitly closed.  However, all sockets will be closed
102 	 * automatically when a process is killed or terminates normally.
103 	 */
104 }
105