Added mention of AF_INET6 address family.

Added discussion of sockaddr structure and an example in the Unix domain.

man2/bind.2

@@ -101,6 +101,10 @@ the manual entries in Section 7 for detailed information. For
 see
 .BR ip (7),
 for
+.B AF_INET6
+see
+.BR ipv6 (7),
+for
 .B AF_UNIX
 see
 .BR unix (7),
@@ -121,6 +125,56 @@ and for
 see
 .BR netlink (7).
 
+The actual structure passed for the
+.I my_addr 
+argument will depend on the address family.
+The
+.I sockaddr
+structure is defined as something like:
+.in +0.25in
+.nf
+
+struct sockaddr {
+    sa_family_t sa_family;
+    char        sa_data[14];
+}
+
+.fi
+.in -0.25in
+The only purpose of this structure is to cast the structure 
+pointer passed in 
+.I my_addr 
+in order to avoid compiler warnings.  
+The following example shows how this is done when binding a socket 
+in the Unix 
+.RB ( AF_UNIX )
+domain:
+
+.in +0.25in
+.nf
+#include <sys/socket.h>
+#include <sys/un.h>
+
+int sfd;
+struct sockaddr_un addr;
+
+sfd = socket(AF_UNIX, SOCK_STREAM, 0);         
+if (sfd == -1) { perror("socket"); exit(EXIT_FAILURE); }
+
+memset(&addr, 0, sizeof(struct sockaddr_un));  
+                        /* Clear structure */
+addr.sun_family = AF_UNIX;                     
+strncpy(addr.sun_path, MY_SOCK_PATH, 
+        sizeof(addr.sun_path) - 1);
+
+if (bind(sfd, (struct sockaddr *) &addr,
+        sizeof(struct sockaddr_un)) == -1) { 
+    perror("bind"); 
+    exit(EXIT_FAILURE); 
+}
+
+.fi
+.in -0.25in
 .SH "RETURN VALUE"
 On success, zero is returned.  On error, \-1 is returned, and
 .I errno
@@ -218,4 +272,6 @@ See also
 .BR socket (2),
 .BR getaddrinfo (3),
 .BR ip (7),
-.BR socket (7)
+.BR ipv6 (7),
+.BR socket (7),
+.BR unix (7)