Trouble with starting XWin, "(EE) Can't read lock file /tmp/.XO-lock"

[Fergus Daly]

-----Original Message-----
From: Cygwin <cygwin-bounces@cygwin.com> On Behalf Of rtroy@ScienceTools.com
Sent: 18 November 2020 22:03
To: cygwin@cygwin.com
Subject: Trouble with starting XWin, "(EE) Can't read lock file /tmp/.XO-lock"

Hey everyone,
SUPER long time Cygwin user, seldom need help, and my versions are all ancient now and I can't upgrade, I don't think. I'm on Windows 7 and am stuck there. Other version data follows.
Everything had been working fine for years, then I had a system crash and on restart, this is the only error I can find.
When run from the Cygwin shell command line, it goes like this:
========
$ XWin :0 -multiwindow -clipboard -wgl -ac -listen tcp Welcome to the XWin X Server
Vendor: The Cygwin/X Project
Release: 1.19.2.0
OS: CYGWIN_NT-6.1 Okrasa 2.8.0(0.309/5/3) 2017-04-01 20:47 x86_64
OS: Windows 7 Service Pack 1 [Windows NT 6.1 build 7601] (Win64)
Package: version 1.19.2-1 built 2017-03-09
XWin was started with the following command line:
XWin :0 -multiwindow -clipboard -wgl -ac -listen tcp
(EE) Fatal server error:
(EE) Could not create lock file in /tmp/.tX0-lock winDeinitMultiWindowWM - Noting shutdown in progress $
========
I tried with window IDs 1 and 2 instead of zero but these didn't work either.
Later, while busy with other things, there was a power failure for the facility and when the power came back on, of course the system had rebooted so I tried again and got the same thing.
...Somehow early in my testing to get this going, without intentionally doing anything else, I noticed the error changed from "Could not create lock file in", to "Can't read lock file /tmp/.X0-lock".
Looking for the directory previously mentioned, it wasn't there so I decided to try and create that directory. When I do that, the error goes back to "Could not create lockfile in". ... I wonder if I created it with the right ownership and permissions, so I tried several things with no success.
...I'm rather desperate to fix this as this feature has become a key tool for this particular system. Ideas? Help?
Thanks,
RT

Also a long-time W7 user: try deleting everything X-relevant under /tmp/
(in my case .X11-unix/ and its contents) and then
$ run XWin -clipboard -nolock -multiwindow <Enter>
I know, simpler than yours - but this has evolved over the years,
replacing earlier more complex command lines which suddenly broke,
usually after some relevant update.
Any good?
BUT NB I am Cygwin-current - what's your difficulty with updating?
Fergus