I get this every 5-10 minutes, and x11vnc crashes and needs to be restarted.

[xcb] Unknown sequence number while processing queue
[xcb] Most likely this is a multi-threaded client and XInitThreads has not been called
[xcb] Aborting, sorry about that.
x11vnc: xcb_io.c:260: poll_for_event: Assertion `!xcb_xlib_threads_sequence_lost' failed.
caught signal: 6
25/10/2019 08:00:07 deleted 120 tile_row polling images.
extra[1] signal: -1
XIO: fatal IO error 11 (Resource temporarily unavailable) on X server ":0"
after 757003 requests (757003 known processed) with 0 events remaining.

Slackware current
x11vnc: 0.9.16

It's been doing this for several weeks, I don't really remember exactly when it started. Prior to this, it never crashed, and was rock solid. Now I can't go ten minutes without this happening. It's possible I updated something that broke this, but don't really know what.

I've tried the slackbuilds version, and I've compiled from scratch. Same result. A romp through google-land shows the error to not be uncommon, but no real fixes related to x11vnc.

Does 'ldd /path/to/x1vnc |grep found' throw up anything? If so, it's missing.

If not, I'd look at restricting cores used. Does anyone else have this problem? Have you googled it?

Somewhat apples and oranges, but I'm using 0.9.14 on 14.2. Perhaps try version 0.9.14 and see what happens.

I autostart x11vnc with the following:

x11vnc -nevershared -forever -no6 -noipv6 -rfbport 5900 -rfbportv6 -1 -o .x11vnc

I did that already - long list of dependencies, and nothing missing.

Good advice - I'll do that and report back in a few days...

I've searched and searched. While the error itself is not uncommon, I have not found anyone reporting it with respect to x11vnc. (lucky me).

I downgraded to 0.9.15 and it hasn't crashed yet (knock on wood). Maybe this is a problem specific to 0.9.16?

So sadly this crash has persisted. I downgraded to 0.9.14, and it is still doing the same thing. I'm kinda at a loss here, this used to be 100% rock solid. I'm using Slackware-current, and I'm wondering if some update that was pushed in the last month or so is causing this? x11vnc itself doesn't seem to have changed, I've been using this version for a few years.

Ok, next you run 'ldd /path/to/x11vnc'

Look at all those libs it throws up. It may beone of them that's causing the issue

Well somewhere along the line I finally realized I was using -threads. I changed that to -nothreads and the problem went away.

So the moral of the story - make sure that the problem isn't just something you stupidly did to yourself....

IDK if -threads should work or not, but for me it seems to be the cause of the problem.