+static int initdisc = -1; /* Initial TTY discipline for ppp_fd */
+static int initfdflags = -1; /* Initial file descriptor flags for ppp_fd */
+static int ppp_fd = -1; /* fd which is set to PPP discipline */
+
+static int restore_term; /* 1 => we've munged the terminal */
+static struct termios inittermios; /* Initial TTY termios */
+static struct winsize wsinfo; /* Initial window size info */
+
+static char *lock_file; /* name of lock file created */
+
+static int loop_slave = -1;
+static int loop_master;
+static char loop_name[20];
+
+static unsigned char inbuf[512]; /* buffer for chars read from loopback */
+
+static int sockfd; /* socket for doing interface ioctls */
+
+static int if_is_up; /* the interface is currently up */
+static u_int32_t ifaddrs[2]; /* local and remote addresses */
+static u_int32_t default_route_gateway; /* gateway addr for default route */
+static u_int32_t proxy_arp_addr; /* remote addr for proxy arp */
+
+/* Prototypes for procedures local to this file. */
+static int translate_speed __P((int));
+static int baud_rate_of __P((int));
+static int get_ether_addr __P((u_int32_t, struct sockaddr *));
+
+
+/*
+ * sys_init - System-dependent initialization.
+ */
+void
+sys_init()
+{
+ /* Get an internet socket for doing socket ioctl's on. */
+ if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+ syslog(LOG_ERR, "Couldn't create IP socket: %m");
+ die(1);
+ }
+}
+
+/*
+ * sys_cleanup - restore any system state we modified before exiting:
+ * mark the interface down, delete default route and/or proxy arp entry.
+ * This should call die() because it's called from die().
+ */
+void
+sys_cleanup()
+{
+ struct ifreq ifr;
+
+ if (if_is_up) {
+ strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
+ if (ioctl(sockfd, SIOCGIFFLAGS, &ifr) >= 0
+ && ((ifr.ifr_flags & IFF_UP) != 0)) {
+ ifr.ifr_flags &= ~IFF_UP;
+ ioctl(sockfd, SIOCSIFFLAGS, &ifr);
+ }
+ }
+ if (ifaddrs[0])
+ cifaddr(0, ifaddrs[0], ifaddrs[1]);
+ if (default_route_gateway)
+ cifdefaultroute(0, 0, default_route_gateway);
+ if (proxy_arp_addr)
+ cifproxyarp(0, proxy_arp_addr);
+}
+
+/*
+ * sys_close - Clean up in a child process before execing.
+ */
+void
+sys_close()
+{
+ close(sockfd);
+ if (loop_slave >= 0) {
+ close(loop_slave);
+ close(loop_master);
+ }
+}
+
+/*
+ * sys_check_options - check the options that the user specified
+ */
+void
+sys_check_options()
+{
+ if (demand) {
+ option_error("Sorry - demand-dialling is not supported under Ultrix\n");
+ exit(1);
+ }
+}
+
+
+/*
+ * daemon - Detach us from the terminal session.
+ */
+int
+daemon(nochdir, noclose)
+ int nochdir, noclose;
+{
+ int pid;
+
+ if ((pid = fork()) < 0)
+ return -1;
+ if (pid != 0)
+ exit(0); /* parent dies */
+ setsid();
+ if (!nochdir)
+ chdir("/");
+ if (!noclose) {
+ fclose(stdin); /* don't need stdin, stdout, stderr */
+ fclose(stdout);
+ fclose(stderr);
+ }
+ return 0;
+}
+
+/*
+ * ppp_available - check whether the system has any ppp interfaces
+ * (in fact we check whether we can do an ioctl on ppp0).
+ */
+int
+ppp_available()
+{
+ int s, ok;
+ struct ifreq ifr;
+ extern char *no_ppp_msg;
+
+ if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
+ return 1; /* can't tell */
+
+ strncpy(ifr.ifr_name, "ppp0", sizeof (ifr.ifr_name));
+ ok = ioctl(s, SIOCGIFFLAGS, (caddr_t) &ifr) >= 0;
+ close(s);
+
+ no_ppp_msg = "\
+This system lacks kernel support for PPP. To include PPP support\n\
+in the kernel, please follow the steps detailed in the README.ultrix\n\
+file in the ppp-2.2 distribution.\n";
+ return ok;
+}