#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\n", 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\n");
               else
                    printf("-->%s\n", 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);
}