Index: ange-ftp.el
===================================================================
RCS file: /cvsroot/emacs/emacs/lisp/net/ange-ftp.el,v
retrieving revision 1.80
diff -u -r1.80 ange-ftp.el
--- ange-ftp.el	6 Feb 2006 11:33:04 -0000	1.80
+++ ange-ftp.el	11 Nov 2006 14:22:59 -0000
@@ -1641,10 +1641,43 @@
 ;; Build up a complete line of output from the ftp PROCESS and pass it
 ;; on to ange-ftp-process-handle-line to deal with.
 
+(defvar ange-ftp-proc-trace nil)
+(defvar ange-ftp-proc-trace-on nil)
+;;(setq ange-ftp-proc-trace-on t) <-
+(defun ange-ftp-add-to-proc-trace(str)
+  (when ange-ftp-proc-trace-on
+    (setq ange-ftp-proc-trace (cons str ange-ftp-proc-trace))))
+(defun ange-ftp-show-proc-trace()
+  (interactive)
+  (let ((buf (get-buffer-create "ange-ftp-proc-trace")))
+    (with-current-buffer buf
+      (erase-buffer)
+      (insert (format "%s" (apply 'concat ange-ftp-proc-trace))))
+    (switch-to-buffer-other-window buf)))
+
 (defun ange-ftp-process-filter (proc str)
   ;; Eliminate nulls.
-  (while (string-match "\000+" str)
-    (setq str (replace-match "" nil nil str)))
+  ;;
+  ;; Also check if the ftp process seems ok.  If it is not ok throw
+  ;; `ange-ftp-proc-defunct' which will be caught by
+  ;; `ange-ftp-raw-send' that will then restart the ftp process.
+  ;;
+  ;; On w32 when the ftp program from gnu
+  ;; (ftp://ftp.gnu.org/old-gnu/emacs/windows/contrib/ftp-for-win32.zip)
+  ;; is used Emacs will read a string consisting of only nulls after
+  ;; the ftp program has timed out.  The only way I have found to cure
+  ;; this is to delete the ftp process.
+  (ange-ftp-add-to-proc-trace (format "str=%s\n" str))
+  (let ((str-len (length str)))
+    (while (string-match "\000+" str)
+      (setq str (replace-match "" nil nil str)))
+    (when (and (boundp 'ange-ftp-check-proc-ok)
+               ange-ftp-check-proc-ok
+               (cond ((eq system-type 'windows-nt)
+                      (and
+                       (= 0 (length str))
+                       (< 20 str-len)))))
+      (throw 'ange-ftp-proc-defunct t)))
 
   ;; see if the buffer is still around... it could have been deleted.
   (when (buffer-live-p (process-buffer proc))
@@ -2277,7 +2310,9 @@
 	(ange-ftp-this-user user)
 	(ange-ftp-this-host host)
 	(ange-ftp-this-msg msg)
-	cmd2 cmd3 host-type fix-name-func result)
+	cmd2 cmd3 host-type fix-name-func result
+        (sent-sts nil)
+        (sent-res nil))
 
     (cond
 
@@ -2365,37 +2400,55 @@
 		      (and cmd2 (concat " " cmd2))))
 
     ;; Actually send the resulting command.
-    (if (and (consp result) (null (car result)))
-	;; `ange-ftp-cd' has failed, so there's no point sending `cmd'.
-	result
-      (let (afsc-result
-	    afsc-line)
-	(ange-ftp-raw-send-cmd
-	 (ange-ftp-get-process host user)
-	 cmd
-	 msg
-	 (list (lambda (result line host user cmd msg cont nowait)
-		 (or cont (setq afsc-result result
-				afsc-line line))
-		 (if result (ange-ftp-call-cont cont result line)
-                   (ange-ftp-raw-send-cmd
-                    (ange-ftp-get-process host user)
-                    cmd
-                    msg
-                    (list (lambda (result line cont)
-                            (or cont (setq afsc-result result
-                                           afsc-line line))
-                            (ange-ftp-call-cont cont result line))
-                          cont)
-		    nowait)))
-	       host user cmd msg cont nowait)
-	 nowait)
-
-	(if nowait
-	    nil
-	  (if cont
-	      nil
-	    (cons afsc-result afsc-line)))))))
+    (while (memq sent-sts '(nil tried))
+      (when (eq sent-sts 'tried)
+        ;; Delete ftp process if send failed before, it will be
+        ;; restarted by `ange-ftp-get-process'.
+        (message "Ftp process possibly defunct, deleting it ...")
+        (ange-ftp-add-to-proc-trace "\n********* DEFUNCT killing ftp process\\n")
+        (let* ((proc (ange-ftp-get-process host user))
+               (delete-exited-processes t))
+          (delete-process proc)))
+      (if (and (consp result) (null (car result)))
+          ;; `ange-ftp-cd' has failed, so there's no point sending `cmd'.
+          (progn
+            (setq sent-res result)
+            (setq sent-sts 'failed))
+        (let (afsc-result
+              afsc-line
+              (ange-ftp-check-proc-ok (not nowait)))
+          (catch 'ange-ftp-proc-defunct
+            (setq sent-sts 'tried)
+            ;; May throw 'ange-ftp-proc-defunct:
+            (ange-ftp-add-to-proc-trace (format "cmd=%s\n" cmd))
+            (ange-ftp-raw-send-cmd
+             (ange-ftp-get-process host user)
+             cmd
+             msg
+             (list (lambda (result line host user cmd msg cont nowait)
+                     (or cont (setq afsc-result result
+                                    afsc-line line))
+                     (if result (ange-ftp-call-cont cont result line)
+                       (ange-ftp-raw-send-cmd
+                        (ange-ftp-get-process host user)
+                        cmd
+                        msg
+                        (list (lambda (result line cont)
+                                (or cont (setq afsc-result result
+                                               afsc-line line))
+                                (ange-ftp-call-cont cont result line))
+                              cont)
+                        nowait)))
+                   host user cmd msg cont nowait)
+             nowait)
+
+            (setq sent-sts 'ok)
+            (if nowait
+                (setq sent-res nil)
+              (if cont
+                  (setq sent-res nil)
+                (setq sent-res (cons afsc-result afsc-line))))))))
+    sent-res))
 
 ;; It might be nice to message users about the host type identified,
 ;; but there is so much other messaging going on, it would not be