xref: /freebsd/share/doc/psd/20.ipctut/ustreamread.c (revision ae83180158c4c937f170e31eff311b18c0286a93)
1 .\" Copyright (c) 1986, 1993
2 .\"	The Regents of the University of California.  All rights reserved.
3 .\"
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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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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 .\"	@(#)ustreamread.c	8.1 (Berkeley) 6/8/93
33 .\"
34 #include <sys/types.h>
35 #include <sys/socket.h>
36 #include <sys/un.h>
37 #include <stdio.h>
38 
39 #define NAME "socket"
40 
41 /*
42  * This program creates a socket in the UNIX domain and binds a name to it.
43  * After printing the socket's name it begins a loop. Each time through the
44  * loop it accepts a connection and prints out messages from it.  When the
45  * connection breaks, or a termination message comes through, the program
46  * accepts a new connection.
47  */
48 main()
49 {
50 	int sock, msgsock, rval;
51 	struct sockaddr_un server;
52 	char buf[1024];
53 
54 	/* Create socket */
55 	sock = socket(AF_UNIX, SOCK_STREAM, 0);
56 	if (sock < 0) {
57 		perror("opening stream socket");
58 		exit(1);
59 	}
60 	/* Name socket using file system name */
61 	server.sun_family = AF_UNIX;
62 	strcpy(server.sun_path, NAME);
63 	if (bind(sock, &server, sizeof(struct sockaddr_un))) {
64 		perror("binding stream socket");
65 		exit(1);
66 	}
67 	printf("Socket has name %s\en", server.sun_path);
68 	/* Start accepting connections */
69 	listen(sock, 5);
70 	for (;;) {
71 		msgsock = accept(sock, 0, 0);
72 		if (msgsock == -1)
73 			perror("accept");
74 		else do {
75 			bzero(buf, sizeof(buf));
76 			if ((rval = read(msgsock, buf, 1024)) < 0)
77 				perror("reading stream message");
78 			else if (rval == 0)
79 				printf("Ending connection\en");
80 			else
81 				printf("-->%s\en", buf);
82 		} while (rval > 0);
83 		close(msgsock);
84 	}
85 	/*
86 	 * The following statements are not executed, because they follow an
87 	 * infinite loop.  However, most ordinary programs will not run
88 	 * forever.  In the UNIX domain it is necessary to tell the file
89 	 * system that one is through using NAME.  In most programs one uses
90 	 * the call unlink() as below. Since the user will have to kill this
91 	 * program, it will be necessary to remove the name by a command from
92 	 * the shell.
93 	 */
94 	close(sock);
95 	unlink(NAME);
96 }
97