* lisp/gnus/nnimap.el (nnimap-open-connection-1): Use tcp-keealive if possible.

2 files changed, 12 insertions, 0 deletions

diff --git a/lisp/gnus/ChangeLog b/lisp/gnus/ChangeLog
index 12cbd30df68..3fb44bb5b10 100644
--- a/lisp/gnus/ChangeLog
+++ b/lisp/gnus/ChangeLog
@@ -1,3 +1,7 @@
+2011-11-03  Stefan Monnier  <monnier@iro.umontreal.ca>
+
+        * nnimap.el (nnimap-open-connection-1): Use tcp-keealive if possible.
+
 2011-11-02  Teodor Zlatanov  <tzz@lifelogs.com>
 
         * gnus-util.el (gnus-bound-and-true-p): Another comment to explain why
diff --git a/lisp/gnus/nnimap.el b/lisp/gnus/nnimap.el
index 77372c246cb..cda17ba57c6 100644
--- a/lisp/gnus/nnimap.el
+++ b/lisp/gnus/nnimap.el
@@ -397,6 +397,14 @@ textual parts.")
              (stream-type (plist-get props :type)))
         (when (and stream (not (memq (process-status stream) '(open run))))
           (setq stream nil))
+
+        (when (and (fboundp 'set-network-process-option) ;; Not in XEmacs.
+                   (fboundp 'process-type) ;; Emacs 22 doesn't provide it.
+                   (eq (process-type stream) 'network))
+          ;; Use TCP-keepalive so that connections that pass through a NAT
+          ;; router don't hang when left idle.
+          (set-network-process-option stream :keepalive t))
+
         (setf (nnimap-process nnimap-object) stream)
         (setf (nnimap-stream-type nnimap-object) stream-type)
         (if (not stream)