assistant --autostart: First any daemons that are already running, which might be left over from a previous login session and so unable to use the ssh agent of a new login session.

Command/Assistant.hs

@@ -91,6 +91,12 @@ autoStart startdelay = do
   where
 	go haveionice program dir = do
 		setCurrentDirectory dir
+		-- First stop any old daemon running in this directory, which
+		-- might be a leftover from an old login session. Such a
+		-- leftover might be left in an environment where it is
+		-- unavble to use the ssh agent or other login session
+		-- resources.
+		void $ boolSystem program [Param "assistant", Param "--stop"]
 		if haveionice
 			then boolSystem "ionice" (Param "-c3" : Param program : baseparams)
 			else boolSystem program baseparams

debian/changelog

@@ -1,6 +1,9 @@
 git-annex (5.20150618) UNRELEASED; urgency=medium
 
   * log: Fix reversion introduced in version 5.20150528 that broke this command.
+  * assistant --autostart: First any daemons that are already running,
+    which might be left over from a previous login session and so unable to
+    use the ssh agent of a new login session.
 
  -- Joey Hess <id@joeyh.name>  Thu, 02 Jul 2015 12:31:14 -0400
 

doc/bugs/kill_git-annex_assistant_on_logout.mdwn

@@ -1,3 +1,29 @@
 When you logout of any x session git-annex does not get killed.
 This means that if you login again git-annex will still try to use the ssh-agent from the last session which doesn't run anymore.
 This leads to countless password queries unless you use a passwordless key.
+
+> I've fixed this, though maybe not in an ideal way.
+> 
+> There's no way to make a XDG desktop file run a command on logout, that I
+> can see. That would have been my first choice.
+> 
+> So, I thought I'd just have the assistant not run setsid, so it's part of
+> the current login session and would get killed automatically on logout. 
+> I was surprised that this didn't seem to work, on a system using logind.
+> Even when the desktop file ran git-annex with --foreground, it was not
+> stopped on logout. This may be because logind defaults to
+> KillUserProcesses=false,
+> although I'm not sure why processes that are part of the login session
+> are not killed at least.
+> 
+> What I have settled on is to leave the daemon running after logout, 
+> but on a new login have the `git annex assistant --autostart` kill the
+> old daemon and start a new one.
+> 
+> Only possible problem with that is there will be a small window after
+> login where the old daemon is running. It might slip in a password prompt
+> there, using the new DISPLAY. At least it won't flood, and even a single
+> password prompt is pretty unlikely.
+> 
+> I am tenatively going to call this [[done]]. Seems to me that logind
+> could be improved though. --[[Joey]]