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diff --git a/share/doc/psd/20.ipctut/ustreamread.c b/share/doc/psd/20.ipctut/ustreamread.c
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+++ b/share/doc/psd/20.ipctut/ustreamread.c
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+.\" Copyright (c) 1986, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed by the University of
+.\"	California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	@(#)ustreamread.c	8.1 (Berkeley) 6/8/93
+.\"
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <stdio.h>
+
+#define NAME "socket"
+
+/*
+ * This program creates a socket in the UNIX domain and binds a name to it. 
+ * After printing the socket's name it begins a loop. Each time through the
+ * loop it accepts a connection and prints out messages from it.  When the
+ * connection breaks, or a termination message comes through, the program
+ * accepts a new connection. 
+ */
+main()
+{
+	int sock, msgsock, rval;
+	struct sockaddr_un server;
+	char buf[1024];
+
+	/* Create socket */
+	sock = socket(AF_UNIX, SOCK_STREAM, 0);
+	if (sock < 0) {
+		perror("opening stream socket");
+		exit(1);
+	}
+	/* Name socket using file system name */
+	server.sun_family = AF_UNIX;
+	strcpy(server.sun_path, NAME);
+	if (bind(sock, &server, sizeof(struct sockaddr_un))) {
+		perror("binding stream socket");
+		exit(1);
+	}
+	printf("Socket has name %s\en", server.sun_path);
+	/* Start accepting connections */
+	listen(sock, 5);
+	for (;;) {
+		msgsock = accept(sock, 0, 0);
+		if (msgsock == -1)
+			perror("accept");
+		else do {
+			bzero(buf, sizeof(buf));
+			if ((rval = read(msgsock, buf, 1024)) < 0)
+				perror("reading stream message");
+			else if (rval == 0)
+				printf("Ending connection\en");
+			else
+				printf("-->%s\en", buf);
+		} while (rval > 0);
+		close(msgsock);
+	}
+	/*
+	 * The following statements are not executed, because they follow an
+	 * infinite loop.  However, most ordinary programs will not run
+	 * forever.  In the UNIX domain it is necessary to tell the file
+	 * system that one is through using NAME.  In most programs one uses
+	 * the call unlink() as below. Since the user will have to kill this
+	 * program, it will be necessary to remove the name by a command from
+	 * the shell. 
+	 */
+	close(sock);
+	unlink(NAME);
+}