xref: /freebsd/share/doc/psd/20.ipctut/streamread.c (revision 641a6cfb86023499caafe26a4d821a0b885cf00b)
1 .\" Copyright (c) 1986, 1993
2 .\"	The Regents of the University of California.  All rights reserved.
3 .\"
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5 .\" modification, are permitted provided that the following conditions
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8 .\"    notice, this list of conditions and the following disclaimer.
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11 .\"    documentation and/or other materials provided with the distribution.
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13 .\"    must display the following acknowledgement:
14 .\"	This product includes software developed by the University of
15 .\"	California, Berkeley and its contributors.
16 .\" 4. Neither the name of the University nor the names of its contributors
17 .\"    may be used to endorse or promote products derived from this software
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31 .\"
32 .\"	@(#)streamread.c	8.1 (Berkeley) 6/8/93
33 .\"
34 #include <sys/types.h>
35 #include <sys/socket.h>
36 #include <netinet/in.h>
37 #include <netdb.h>
38 #include <stdio.h>
39 #define TRUE 1
40 
41 /*
42  * This program creates a socket and then begins an infinite loop. Each time
43  * through the loop it accepts a connection and prints out messages from it.
44  * When the connection breaks, or a termination message comes through, the
45  * program accepts a new connection.
46  */
47 
48 main()
49 {
50 	int sock, length;
51 	struct sockaddr_in server;
52 	int msgsock;
53 	char buf[1024];
54 	int rval;
55 	int i;
56 
57 	/* Create socket */
58 	sock = socket(AF_INET, SOCK_STREAM, 0);
59 	if (sock < 0) {
60 		perror("opening stream socket");
61 		exit(1);
62 	}
63 	/* Name socket using wildcards */
64 	server.sin_family = AF_INET;
65 	server.sin_addr.s_addr = INADDR_ANY;
66 	server.sin_port = 0;
67 	if (bind(sock, &server, sizeof(server))) {
68 		perror("binding stream socket");
69 		exit(1);
70 	}
71 	/* Find out assigned port number and print it out */
72 	length = sizeof(server);
73 	if (getsockname(sock, &server, &length)) {
74 		perror("getting socket name");
75 		exit(1);
76 	}
77 	printf("Socket has port #%d\en", ntohs(server.sin_port));
78 
79 	/* Start accepting connections */
80 	listen(sock, 5);
81 	do {
82 		msgsock = accept(sock, 0, 0);
83 		if (msgsock == -1)
84 			perror("accept");
85 		else do {
86 			bzero(buf, sizeof(buf));
87 			if ((rval = read(msgsock, buf, 1024)) < 0)
88 				perror("reading stream message");
89 			i = 0;
90 			if (rval == 0)
91 				printf("Ending connection\en");
92 			else
93 				printf("-->%s\en", buf);
94 		} while (rval != 0);
95 		close(msgsock);
96 	} while (TRUE);
97 	/*
98 	 * Since this program has an infinite loop, the socket "sock" is
99 	 * never explicitly closed.  However, all sockets will be closed
100 	 * automatically when a process is killed or terminates normally.
101 	 */
102 }
103