diff --git a/usr.sbin/ppp/async.c b/usr.sbin/ppp/async.c
index 482baa157a4c..8bf8d187144d 100644
--- a/usr.sbin/ppp/async.c
+++ b/usr.sbin/ppp/async.c
@@ -17,7 +17,7 @@
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * $Id: async.c,v 1.15.2.4 1998/02/02 19:33:29 brian Exp $
+ * $Id: async.c,v 1.15.2.5 1998/02/08 11:04:40 brian Exp $
  *
  */
 #include <sys/param.h>
@@ -42,6 +42,7 @@
 #include "async.h"
 #include "throughput.h"
 #include "link.h"
+#include "descriptor.h"
 #include "physical.h"
 
 #define MODE_HUNT 0x01
diff --git a/usr.sbin/ppp/auth.c b/usr.sbin/ppp/auth.c
index 0f2793da3943..e60098302f6c 100644
--- a/usr.sbin/ppp/auth.c
+++ b/usr.sbin/ppp/auth.c
@@ -17,7 +17,7 @@
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * $Id: auth.c,v 1.27.2.5 1998/02/02 19:33:33 brian Exp $
+ * $Id: auth.c,v 1.27.2.6 1998/02/07 20:49:18 brian Exp $
  *
  *	TODO:
  *		o Implement check against with registered IP addresses.
@@ -48,6 +48,7 @@
 #include "hdlc.h"
 #include "async.h"
 #include "link.h"
+#include "descriptor.h"
 #include "physical.h"
 #include "lcpproto.h"
 
diff --git a/usr.sbin/ppp/bundle.c b/usr.sbin/ppp/bundle.c
index b14230f5a29d..a15c091b5c9b 100644
--- a/usr.sbin/ppp/bundle.c
+++ b/usr.sbin/ppp/bundle.c
@@ -23,7 +23,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	$Id: bundle.c,v 1.1.2.5 1998/02/07 20:49:23 brian Exp $
+ *	$Id: bundle.c,v 1.1.2.6 1998/02/08 19:29:43 brian Exp $
  */
 
 #include <sys/param.h>
@@ -64,6 +64,7 @@
 #include "lcp.h"
 #include "ccp.h"
 #include "async.h"
+#include "descriptor.h"
 #include "physical.h"
 #include "modem.h"
 #include "main.h"
diff --git a/usr.sbin/ppp/chap.c b/usr.sbin/ppp/chap.c
index 8da76a6d25fc..6ec99a87be86 100644
--- a/usr.sbin/ppp/chap.c
+++ b/usr.sbin/ppp/chap.c
@@ -17,7 +17,7 @@
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * $Id: chap.c,v 1.28.2.6 1998/02/02 19:33:33 brian Exp $
+ * $Id: chap.c,v 1.28.2.7 1998/02/07 20:49:30 brian Exp $
  *
  *	TODO:
  */
@@ -59,6 +59,7 @@
 #include "async.h"
 #include "throughput.h"
 #include "link.h"
+#include "descriptor.h"
 #include "physical.h"
 #include "bundle.h"
 
diff --git a/usr.sbin/ppp/chat.c b/usr.sbin/ppp/chat.c
index 767b1dcd0b86..d0d096e2d918 100644
--- a/usr.sbin/ppp/chat.c
+++ b/usr.sbin/ppp/chat.c
@@ -18,7 +18,7 @@
  *		Columbus, OH  43221
  *		(614)451-1883
  *
- * $Id: chat.c,v 1.44.2.3 1998/02/06 02:22:07 brian Exp $
+ * $Id: chat.c,v 1.44.2.4 1998/02/06 02:23:30 brian Exp $
  *
  *  TODO:
  *	o Support more UUCP compatible control sequences.
@@ -55,6 +55,7 @@
 #include "lcp.h"
 #include "link.h"
 #include "async.h"
+#include "descriptor.h"
 #include "physical.h"
 #include "chat.h"
 
diff --git a/usr.sbin/ppp/command.c b/usr.sbin/ppp/command.c
index 68cf14a764d9..6f0ca63360a5 100644
--- a/usr.sbin/ppp/command.c
+++ b/usr.sbin/ppp/command.c
@@ -17,7 +17,7 @@
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * $Id: command.c,v 1.131.2.10 1998/02/06 02:24:09 brian Exp $
+ * $Id: command.c,v 1.131.2.11 1998/02/07 20:49:32 brian Exp $
  *
  */
 #include <sys/param.h>
@@ -75,6 +75,7 @@
 #include "auth.h"
 #include "async.h"
 #include "link.h"
+#include "descriptor.h"
 #include "physical.h"
 
 struct in_addr ifnetmask;
diff --git a/usr.sbin/ppp/descriptor.h b/usr.sbin/ppp/descriptor.h
new file mode 100644
index 000000000000..37a8fd4d8ca2
--- /dev/null
+++ b/usr.sbin/ppp/descriptor.h
@@ -0,0 +1,44 @@
+/*-
+ * Copyright (c) 1998 Brian Somers <brian@Awfulhak.org>
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ *
+ *	$Id$
+ */
+
+#define PHYSICAL_DESCRIPTOR (1)
+
+struct descriptor {
+  int type;
+  struct descriptor *next;
+
+  int (*UpdateSet)(struct descriptor *, fd_set *, fd_set *, fd_set *, int *);
+  int (*IsSet)(struct descriptor *, fd_set *);
+  void (*Read)(struct descriptor *, struct bundle *);
+  void (*Write)(struct descriptor *);
+};
+
+#define descriptor_UpdateSet(d, r, w, e, n) ((*(d)->UpdateSet)(d, r, w, e, n))
+#define descriptor_IsSet(d, s) ((*(d)->IsSet)(d, s))
+#define descriptor_Read(d, b) ((*(d)->Read)(d, b))
+#define descriptor_Write(d) ((*(d)->Write)(d))
diff --git a/usr.sbin/ppp/fsm.c b/usr.sbin/ppp/fsm.c
index eff97ae79d03..b87bf28314dc 100644
--- a/usr.sbin/ppp/fsm.c
+++ b/usr.sbin/ppp/fsm.c
@@ -17,7 +17,7 @@
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * $Id: fsm.c,v 1.27.2.7 1998/02/06 02:24:10 brian Exp $
+ * $Id: fsm.c,v 1.27.2.8 1998/02/07 20:49:35 brian Exp $
  *
  *  TODO:
  *		o Refer loglevel for log output
@@ -47,6 +47,7 @@
 #include "throughput.h"
 #include "async.h"
 #include "link.h"
+#include "descriptor.h"
 #include "physical.h"
 #include "bundle.h"
 
diff --git a/usr.sbin/ppp/hdlc.c b/usr.sbin/ppp/hdlc.c
index 26baf00dc0f2..a26185db2861 100644
--- a/usr.sbin/ppp/hdlc.c
+++ b/usr.sbin/ppp/hdlc.c
@@ -17,7 +17,7 @@
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * $Id: hdlc.c,v 1.28.2.6 1998/02/02 19:33:35 brian Exp $
+ * $Id: hdlc.c,v 1.28.2.7 1998/02/07 20:49:36 brian Exp $
  *
  *	TODO:
  */
@@ -51,6 +51,7 @@
 #include "modem.h"
 #include "ccp.h"
 #include "link.h"
+#include "descriptor.h"
 #include "physical.h"
 
 static struct hdlcstat {
@@ -559,3 +560,34 @@ HdlcInput(struct bundle *bundle, struct mbuf * bp, struct physical *physical)
 
   DecodePacket(bundle, proto, bp, physical2link(physical));
 }
+
+/*
+ *  Detect a HDLC frame
+ */
+
+static const char *FrameHeaders[] = {
+  "\176\377\003\300\041",
+  "\176\377\175\043\300\041",
+  "\176\177\175\043\100\041",
+  "\176\175\337\175\043\300\041",
+  "\176\175\137\175\043\100\041",
+  NULL,
+};
+
+u_char *
+HdlcDetect(struct physical *physical, u_char *cp, int n)
+{
+  const char *ptr, *fp, **hp;
+
+  cp[n] = '\0';			/* be sure to null terminated */
+  ptr = NULL;
+  for (hp = FrameHeaders; *hp; hp++) {
+    fp = *hp;
+    if (Physical_IsSync(physical))
+      fp++;
+    ptr = strstr((char *) cp, fp);
+    if (ptr)
+      break;
+  }
+  return (u_char *)ptr;
+}
diff --git a/usr.sbin/ppp/hdlc.h b/usr.sbin/ppp/hdlc.h
index 9eb29175d1ef..89bf74260f83 100644
--- a/usr.sbin/ppp/hdlc.h
+++ b/usr.sbin/ppp/hdlc.h
@@ -15,7 +15,7 @@
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * $Id: hdlc.h,v 1.14.2.2 1998/01/30 19:45:42 brian Exp $
+ * $Id: hdlc.h,v 1.14.2.3 1998/02/02 19:32:07 brian Exp $
  *
  *	TODO:
  */
@@ -68,3 +68,4 @@ extern void HdlcOutput(struct link *, int, u_short, struct mbuf *bp);
 extern u_short HdlcFcs(u_short, u_char *, int);
 extern int ReportHdlcStatus(struct cmdargs const *);
 extern int ReportProtStatus(struct cmdargs const *);
+extern u_char *HdlcDetect(struct physical *, u_char *, int);
diff --git a/usr.sbin/ppp/ipcp.c b/usr.sbin/ppp/ipcp.c
index bbeb0f9da062..f444ae8c1178 100644
--- a/usr.sbin/ppp/ipcp.c
+++ b/usr.sbin/ppp/ipcp.c
@@ -17,7 +17,7 @@
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * $Id: ipcp.c,v 1.50.2.10 1998/02/08 11:04:51 brian Exp $
+ * $Id: ipcp.c,v 1.50.2.11 1998/02/08 19:29:44 brian Exp $
  *
  *	TODO:
  *		o More RFC1772 backwoard compatibility
@@ -62,6 +62,7 @@
 #include "hdlc.h"
 #include "async.h"
 #include "link.h"
+#include "descriptor.h"
 #include "physical.h"
 #include "id.h"
 #include "arp.h"
diff --git a/usr.sbin/ppp/lcp.c b/usr.sbin/ppp/lcp.c
index 36848ff61ae0..3b06f7423530 100644
--- a/usr.sbin/ppp/lcp.c
+++ b/usr.sbin/ppp/lcp.c
@@ -17,7 +17,7 @@
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * $Id: lcp.c,v 1.55.2.11 1998/02/07 20:49:44 brian Exp $
+ * $Id: lcp.c,v 1.55.2.12 1998/02/08 11:04:54 brian Exp $
  *
  * TODO:
  *	o Limit data field length by MRU
@@ -65,6 +65,7 @@
 #include "modem.h"
 #include "tun.h"
 #include "link.h"
+#include "descriptor.h"
 #include "physical.h"
 
 /* for received LQRs */
diff --git a/usr.sbin/ppp/lqr.c b/usr.sbin/ppp/lqr.c
index b32f14dbad63..441f9cbbf471 100644
--- a/usr.sbin/ppp/lqr.c
+++ b/usr.sbin/ppp/lqr.c
@@ -17,7 +17,7 @@
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * $Id: lqr.c,v 1.22.2.5 1998/02/02 19:33:37 brian Exp $
+ * $Id: lqr.c,v 1.22.2.6 1998/02/07 20:49:50 brian Exp $
  *
  *	o LQR based on RFC1333
  *
@@ -43,6 +43,7 @@
 #include "async.h"
 #include "throughput.h"
 #include "link.h"
+#include "descriptor.h"
 #include "physical.h"
 #include "bundle.h"
 #include "lqr.h"
diff --git a/usr.sbin/ppp/main.c b/usr.sbin/ppp/main.c
index 084506b1bb3a..072cf51de87d 100644
--- a/usr.sbin/ppp/main.c
+++ b/usr.sbin/ppp/main.c
@@ -17,7 +17,7 @@
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * $Id: main.c,v 1.121.2.14 1998/02/08 11:07:31 brian Exp $
+ * $Id: main.c,v 1.121.2.15 1998/02/08 19:29:45 brian Exp $
  *
  *	TODO:
  *		o Add commands for traffic summary, version display, etc.
@@ -76,6 +76,7 @@
 #include "tun.h"
 #include "route.h"
 #include "link.h"
+#include "descriptor.h"
 #include "physical.h"
 
 #ifndef O_NONBLOCK
@@ -693,38 +694,6 @@ ReadTty(struct bundle *bundle)
   }
 }
 
-
-/*
- *  Here, we'll try to detect HDLC frame
- */
-
-static const char *FrameHeaders[] = {
-  "\176\377\003\300\041",
-  "\176\377\175\043\300\041",
-  "\176\177\175\043\100\041",
-  "\176\175\337\175\043\300\041",
-  "\176\175\137\175\043\100\041",
-  NULL,
-};
-
-static const u_char *
-HdlcDetect(struct physical *physical, u_char * cp, int n)
-{
-  const char *ptr, *fp, **hp;
-
-  cp[n] = '\0';			/* be sure to null terminated */
-  ptr = NULL;
-  for (hp = FrameHeaders; *hp; hp++) {
-    fp = *hp;
-    if (Physical_IsSync(physical))
-      fp++;
-    ptr = strstr((char *) cp, fp);
-    if (ptr)
-      break;
-  }
-  return ((const u_char *) ptr);
-}
-
 static struct pppTimer RedialTimer;
 
 static void
@@ -901,16 +870,8 @@ DoLoop(struct bundle *bundle)
       qlen = link_QueueLen(physical2link(bundle->physical));
     }
 
-    if (link_IsActive(physical2link(bundle->physical))) {
-      /* XXX-ML this should probably be abstracted */
-      if (Physical_GetFD(bundle->physical) + 1 > nfds)
-	nfds = Physical_GetFD(bundle->physical) + 1;
-      Physical_FD_SET(bundle->physical, &rfds);
-      Physical_FD_SET(bundle->physical, &efds);
-      if (qlen > 0) {
-	Physical_FD_SET(bundle->physical, &wfds);
-      }
-    }
+    descriptor_UpdateSet(&bundle->physical->desc, &rfds, &wfds, &efds, &nfds);
+
     if (server >= 0) {
       if (server + 1 > nfds)
 	nfds = server + 1;
@@ -975,7 +936,7 @@ DoLoop(struct bundle *bundle)
       break;
     }
     if ((netfd >= 0 && FD_ISSET(netfd, &efds)) ||
-	(Physical_FD_ISSET(bundle->physical, &efds))) {
+        descriptor_IsSet(&bundle->physical->desc, &efds)) {
       LogPrintf(LogALERT, "Exception detected.\n");
       break;
     }
@@ -1016,50 +977,21 @@ DoLoop(struct bundle *bundle)
       IsInteractive(1);
       Prompt(bundle);
     }
+
     if (netfd >= 0 && FD_ISSET(netfd, &rfds))
       /* something to read from tty */
       ReadTty(bundle);
-    if (Physical_FD_ISSET(bundle->physical, &wfds)) {
+
+    if (descriptor_IsSet(&bundle->physical->desc, &wfds)) {
       /* ready to write into modem */
-      link_StartOutput(physical2link(bundle->physical));
+      descriptor_Write(&bundle->physical->desc);
       if (!link_IsActive(physical2link(bundle->physical)))
         dial_up = 1;
     }
-    if (Physical_FD_ISSET(bundle->physical, &rfds)) {
-      /* something to read from modem */
-      if (LcpInfo.fsm.state <= ST_CLOSED)
-	nointr_usleep(10000);
-      n = Physical_Read(bundle->physical, rbuff, sizeof rbuff);
-      if ((mode & MODE_DIRECT) && n <= 0) {
-        reconnect(RECON_TRUE);
-        link_Close(&bundle->physical->link, bundle, 0);
-      } else
-	LogDumpBuff(LogASYNC, "ReadFromModem", rbuff, n);
 
-      if (LcpInfo.fsm.state <= ST_CLOSED) {
-	/*
-	 * In dedicated mode, we just discard input until LCP is started.
-	 */
-	if (!(mode & MODE_DEDICATED)) {
-	  cp = HdlcDetect(bundle->physical, rbuff, n);
-	  if (cp) {
-	    /*
-	     * LCP packet is detected. Turn ourselves into packet mode.
-	     */
-	    if (cp != rbuff) {
-	      /* XXX missing return value checks */
-	      Physical_Write(bundle->physical, rbuff, cp - rbuff);
-	      Physical_Write(bundle->physical, "\r\n", 2);
-	    }
-	    PacketMode(bundle, 0);
-	  } else if (VarTerm)
-	    write(fileno(VarTerm), rbuff, n);
-	}
-      } else {
-	if (n > 0)
-	  async_Input(bundle, rbuff, n, bundle->physical);
-      }
-    }
+    if (descriptor_IsSet(&bundle->physical->desc, &rfds))
+      descriptor_Read(&bundle->physical->desc, bundle);
+
     if (bundle->tun_fd >= 0 && FD_ISSET(bundle->tun_fd, &rfds)) {
       /* something to read from tun */
       n = read(bundle->tun_fd, &tun, sizeof tun);
diff --git a/usr.sbin/ppp/modem.c b/usr.sbin/ppp/modem.c
index 1fbfa47227e2..3413f4ab0b49 100644
--- a/usr.sbin/ppp/modem.c
+++ b/usr.sbin/ppp/modem.c
@@ -17,7 +17,7 @@
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * $Id: modem.c,v 1.77.2.10 1998/02/07 22:22:45 brian Exp $
+ * $Id: modem.c,v 1.77.2.11 1998/02/08 01:31:27 brian Exp $
  *
  *  TODO:
  */
@@ -66,6 +66,7 @@
 
 /* We're defining a physical device, and thus need the real headers. */
 #include "link.h"
+#include "descriptor.h"
 #include "physical.h"
 
 
@@ -79,6 +80,7 @@ static void modem_StartOutput(struct link *);
 static int modem_IsActive(struct link *);
 static void modem_Hangup(struct link *, int);
 static void modem_Destroy(struct link *);
+static void modem_DescriptorRead(struct descriptor *, struct bundle *);
 
 struct physical *
 modem_Create(const char *name)
@@ -100,6 +102,12 @@ modem_Create(const char *name)
   p->rts_cts = 1;
   p->speed = MODEM_SPEED;
   p->parity = CS8;
+  p->desc.type = PHYSICAL_DESCRIPTOR;
+  p->desc.UpdateSet = Physical_UpdateSet;
+  p->desc.IsSet = Physical_IsSet;
+  p->desc.Read = modem_DescriptorRead;
+  p->desc.Write = Physical_DescriptorWrite;
+
   return p;
 }
 
@@ -977,3 +985,41 @@ int mode;
 
 #endif
 
+static void
+modem_DescriptorRead(struct descriptor *d, struct bundle *bundle)
+{
+  struct physical *p = descriptor2physical(d);
+  u_char rbuff[MAX_MRU], *cp;
+  int n;
+
+  LogPrintf(LogDEBUG, "descriptor2physical; %p -> %p\n", d, p);
+
+  /* something to read from modem */
+  if (LcpInfo.fsm.state <= ST_CLOSED)
+    nointr_usleep(10000);
+
+  n = Physical_Read(p, rbuff, sizeof rbuff);
+  if ((mode & MODE_DIRECT) && n <= 0) {
+    reconnect(RECON_TRUE);
+    link_Close(&p->link, bundle, 0);
+  } else
+    LogDumpBuff(LogASYNC, "ReadFromModem", rbuff, n);
+
+  if (LcpInfo.fsm.state <= ST_CLOSED) {
+    /* In dedicated mode, we just discard input until LCP is started */
+    if (!(mode & MODE_DEDICATED)) {
+      cp = HdlcDetect(p, rbuff, n);
+      if (cp) {
+        /* LCP packet is detected. Turn ourselves into packet mode */
+        if (cp != rbuff) {
+          /* XXX missing return value checks */
+          Physical_Write(p, rbuff, cp - rbuff);
+          Physical_Write(p, "\r\n", 2);
+        }
+        PacketMode(bundle, 0);
+      } else if (VarTerm)
+        write(fileno(VarTerm), rbuff, n);
+    }
+  } else if (n > 0)
+    async_Input(bundle, rbuff, n, p);
+}
diff --git a/usr.sbin/ppp/pap.c b/usr.sbin/ppp/pap.c
index 79f45938550a..5ce19e004fb5 100644
--- a/usr.sbin/ppp/pap.c
+++ b/usr.sbin/ppp/pap.c
@@ -18,7 +18,7 @@
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * $Id: pap.c,v 1.20.2.6 1998/02/02 19:33:39 brian Exp $
+ * $Id: pap.c,v 1.20.2.7 1998/02/07 20:50:01 brian Exp $
  *
  *	TODO:
  */
@@ -54,6 +54,7 @@
 #include "async.h"
 #include "throughput.h"
 #include "link.h"
+#include "descriptor.h"
 #include "physical.h"
 #include "bundle.h"
 
diff --git a/usr.sbin/ppp/physical.c b/usr.sbin/ppp/physical.c
index 4d6fc45ac6f5..9fc9fbdf27ab 100644
--- a/usr.sbin/ppp/physical.c
+++ b/usr.sbin/ppp/physical.c
@@ -16,7 +16,7 @@
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- *  $Id: physical.c,v 1.1.2.4 1998/02/06 02:22:27 brian Exp $
+ *  $Id: physical.c,v 1.1.2.5 1998/02/06 02:23:47 brian Exp $
  *
  */
 
@@ -49,10 +49,12 @@
 #include "async.h"
 #include "link.h"
 
+#include "descriptor.h"
 #include "physical.h"
 
 #include "vars.h"
 #include "bundle.h"
+#include "log.h"
 
 /* External calls - should possibly be moved inline */
 extern int IntToSpeed(int);
@@ -174,3 +176,46 @@ Physical_ReportProtocolStatus(struct cmdargs const *arg)
   link_ReportProtocolStatus(&arg->bundle->physical->link);
   return 0;
 }
+
+int
+Physical_UpdateSet(struct descriptor *d, fd_set *r, fd_set *w, fd_set *e,
+                   int *n)
+{
+  struct physical *p = descriptor2physical(d);
+  int sets;
+
+  LogPrintf(LogDEBUG, "descriptor2physical; %p -> %p\n", d, p);
+
+  if (p->fd >= 0) {
+    if (*n < p->fd + 1)
+      *n = p->fd + 1;
+    FD_SET(p->fd, r);
+    FD_SET(p->fd, e);
+    if (link_QueueLen(&p->link)) {
+      FD_SET(p->fd, w);
+      sets = 3;
+    } else
+      sets = 2;
+  } else
+    sets = 0;
+
+  return sets;
+}
+
+int
+Physical_IsSet(struct descriptor *d, fd_set *fdset)
+{
+  struct physical *p = descriptor2physical(d);
+
+  LogPrintf(LogDEBUG, "descriptor2physical; %p -> %p\n", d, p);
+  return p->fd >= 0 && FD_ISSET(p->fd, fdset);
+}
+
+void
+Physical_DescriptorWrite(struct descriptor *d)
+{
+  struct physical *p = descriptor2physical(d);
+
+  LogPrintf(LogDEBUG, "descriptor2physical; %p -> %p\n", d, p);
+  link_StartOutput(&p->link);
+}
diff --git a/usr.sbin/ppp/physical.h b/usr.sbin/ppp/physical.h
index c98245876d5d..a21e9ddc9edd 100644
--- a/usr.sbin/ppp/physical.h
+++ b/usr.sbin/ppp/physical.h
@@ -16,12 +16,13 @@
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- *  $Id: physical.h,v 1.1.2.4 1998/02/06 02:22:28 brian Exp $
+ *  $Id: physical.h,v 1.1.2.5 1998/02/06 02:24:29 brian Exp $
  *
  */
 
 struct physical {
   struct link link;
+  struct descriptor desc;
   struct async async;          /* Our async state */
   int fd;                      /* File descriptor for this device */
   int mbits;                   /* Current DCD status */
@@ -44,8 +45,16 @@ struct physical {
   struct termios ios;          /* To be able to reset from raw mode */
 };
 
-#define physical2link(p) ((struct link *)p)
-#define link2physical(l) (l->type == PHYSICAL_LINK ? (struct physical *)l : 0)
+#define field2phys(fp, name) \
+  ((struct physical *)((char *)fp - (int)(&((struct physical *)0)->name)))
+
+#define physical2link(p) (&(p)->link)
+#define link2physical(l) \
+  ((l)->type == PHYSICAL_LINK ? field2phys(l, link) : NULL)
+
+#define physical2descriptor(p) (&(p)->desc)
+#define descriptor2physical(d) \
+  ((d)->type == PHYSICAL_DESCRIPTOR ? field2phys(d, desc) : NULL)
 
 int Physical_GetFD(struct physical *);
 int Physical_IsATTY(struct physical *);
@@ -77,3 +86,6 @@ void Physical_DupAndClose(struct physical *);
 ssize_t Physical_Read(struct physical *phys, void *buf, size_t nbytes);
 ssize_t Physical_Write(struct physical *phys, const void *buf, size_t nbytes);
 int Physical_ReportProtocolStatus(struct cmdargs const *);
+int Physical_UpdateSet(struct descriptor *, fd_set *, fd_set *, fd_set *, int *);
+int Physical_IsSet(struct descriptor *, fd_set *);
+void Physical_DescriptorWrite(struct descriptor *);
diff --git a/usr.sbin/ppp/vars.c b/usr.sbin/ppp/vars.c
index b06bdc2ef282..be9fc4834e9f 100644
--- a/usr.sbin/ppp/vars.c
+++ b/usr.sbin/ppp/vars.c
@@ -17,7 +17,7 @@
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * $Id: vars.c,v 1.45.2.3 1998/02/02 19:33:40 brian Exp $
+ * $Id: vars.c,v 1.45.2.4 1998/02/06 02:22:52 brian Exp $
  *
  */
 #include <sys/param.h>
@@ -41,10 +41,11 @@
 #include "async.h"
 #include "throughput.h"
 #include "link.h"
+#include "descriptor.h"
 #include "physical.h"
 
 char VarVersion[] = "PPP Version 1.90";
-char VarLocalVersion[] = "$Date: 1998/02/02 19:33:40 $";
+char VarLocalVersion[] = "$Date: 1998/02/06 02:22:52 $";
 int Utmp = 0;
 int ipKeepAlive = 0;
 int reconnectState = RECON_UNKNOWN;