In trying to get a WinSwitch/xpra server on Ubuntu to work with a WinSwitch/xpra client on OSX, I had to fight with xmodmap a bit (need to use Alt for Eclipse, emacs, etc.). I found the check for running X server not to be quite right. The following diff is for an older version of winswitch/client/client_base.py (I can't use the latest due to ​https://xpra.org/trac/ticket/92), so the lines aren't current but their content hasn't changed.

The first change fixes the search of lines for "org.x.startx". In the old form, line.find returns -1 for any line without a match, triggering on the very first line ("PID Status Label"). Python documentation states a preference for "substring in string", when the position of substring in string is not needed. If you want to insist on "org.x.startx" at the very end of the line, the test could be: if line.endswith("org.x.startx"):

The second change corrects the check for a process that's running now ("0" in parts[1] appears to indicate that the process has terminated and returned 0). Checking that parts[0] is NOT "-" is a valid check for a running process, as well. The man pages are a bit vague.

The changes below work on my MacBookPros at home and at work with 10.5 and 10.6:

432c432
<                                       if line.find("org.x.startx$"):
---
>                                       if "org.x.startx" in line:
436c436
<                                                       started = parts[1]=="0"
---
>                                                       started = parts[1]=="-"

I hope this helps. -Alexey

I've got a remote tunnel, via

ssh -L 8022:host1:22

and connect to host2 via winswitch and the localhost:8022 tunnel.

Now, if I stop that outer SSH session (eg. via the "\n\n~." escape sequence) winswitch sees that the connection is severed, and displays "reconnect" in the servers menu.

But this doesn't work; on the first "reconnect" winswitch says that it couldn't connect, and only on the second try it really reconnects.

So it seems like there's some old state that is not being updated when a connection breaks.

I just installed xpra 0.4.0, and, to get my session upgraded in-place, did a kill of the winswitch_daemon, and reconnected.

winswitch tried to restart xpra, I believe:

26717 ?        S     22:55 /usr/bin/python /usr/bin/xpra --xvfb=/usr/bin/
26718 ?        S      4:55  \_ /usr/bin/Xvfb-for-Xpra-:67 +extension Comp
26786 ?        S      0:00 python /usr/lib/winswitch/delayed_start /home/
26787 ?        S      0:00  \_ /bin/sh -c xchat
26788 ?        Sl    35:13      \_ xchat
13327 ?        S      0:00 /usr/bin/python /usr/bin/winswitch_server --da
13371 ?        D      0:00 /usr/bin/python /usr/bin/xpra --bind-tcp=0.0.0

But something went wrong, and the new session was killed - *including* Xvfb and my active xchat.

The logfile has these entries:

[II] 2012/23/06 22:53:33 XpraServerUtil.start_daemon(ServerSession(:67 - xpra - available),
[II] 2012/23/06 22:53:34 virt_server_daemonizer.grab_daemon_pid(['/.../virt_server_daemonizer', ...
 '--', '/usr/bin/xpra', ... 'start', ':67', '--use-display'
[II] 2012/23/06 22:53:34 XpraServerUtil.session_process_started(13371,ServerSession(:67 - xpra - available))
[II] 2012/23/06 22:53:34 XpraServerUtil.do_watch_session_log(...
[II] 2012/23/06 22:53:34 WinSwitchServer.publish() mDNS_publish=True
[II] 2012/23/06 22:53:34 AvahiPublisher.__init__(Window Switch for ...
[EE] 2012/23/06 22:53:34 AvahiPublishers.start() error on publisher AvahiPublisher(Window Switch for ...
[ee] 2012/23/06 22:53:35 Traceback (most recent call last):
[ee] 2012/23/06 22:53:35   File "/usr/lib/pymodules/python2.7/winswitch/net/avahi_publisher.py", line 64, in start
[ee] 2012/23/06 22:53:35     publisher.start()
[ee] 2012/23/06 22:53:35   File "/usr/lib/pymodules/python2.7/winswitch/net/avahi_publisher.py", line 105, in start
[ee] 2012/23/06 22:53:35     bus = dbus.SystemBus()
[ee] 2012/23/06 22:53:35   File "/usr/lib/python2.7/dist-packages/dbus/_dbus.py", line 194, in __new__
[ee] 2012/23/06 22:53:35     private=private)
[ee] 2012/23/06 22:53:35   File "/usr/lib/python2.7/dist-packages/dbus/_dbus.py", line 100, in __new__
[ee] 2012/23/06 22:53:35     bus = BusConnection.__new__(subclass, bus_type, mainloop=mainloop)
[ee] 2012/23/06 22:53:35   File "/usr/lib/python2.7/dist-packages/dbus/bus.py", line 122, in __new__
[ee] 2012/23/06 22:53:35     bus = cls._new_for_bus(address_or_type, mainloop=mainloop)
[ee] 2012/23/06 22:53:35 DBusException: org.freedesktop.DBus.Error.NoServer:
  Failed to connect to socket /var/run/dbus/system_bus_socket: Connection refused
[II] 2012/23/06 22:53:36 XpraServerUtil.detect_sessions() found: [('DEAD', ':67')]
[II] 2012/23/06 22:53:36 ServerSession.close() self=ServerSession(:67 - xpra - closed), killing ...

Perhaps there's a way to get the new xpra running on a different port, and only grab the Xvfb and kill the old xpra when everything else is ready?