Nested X Server crashes with visual depth mismatch

[Kevin Shea]

Xnest was installed on HP-UX 11 system. Successfully displayed remote nodes with X-windows that use visual depth of 8, but X-windows with visual depth of 24 causes Xnest to crash. Tried the following: set -depth option to visual depth of 24. Now accepts/displays X-windows with visual depth of 24 but not certain windows with visual depth of 8. Also tried -install option (to bypass window manager for colormap install)and -class option (similar to -depth) but neither worked. The local Xserver & window manager (without Xnest in the loop) handles 8 or 24 depth windows just fine. Does anyone have any ideas on how to get around this problem so that I can use the Nested X-server to display windows from remote nodes with either depth?

[Alex Glennie]

good question .... sounds like you've had a good read of the small amount of documetation available for Xnest.

I don't have the time to do any testing today but the graphics card , it's default visual and xdpyinfo output could prove handy .....

do you have an email I could contact you on in case I find the answer a bit later this week ?

also do you see any change in behaviour if the window manager is eliminated ie just test using X: 0 or say xdm mode ? CDE I presume ?

[Charles Slivkoff]

The default behavior of Xnest is to inherit the visual list of its parent. Can you explain the origin of the Xnest that is installed on your system? Was is compiled locally or downloaded from somewhere?

If you require an Xserver which is more flexible with regard to visuals, you might consider Xvnc which runs using a "virtual" frame buffer. Clients for various platforms are available to connect to the Xvnc server. For more details:

http://www.uk.research.att.com/vnc/

[Alex Glennie]

Thanks for replying to this Chuck !

Kevin listen to this guy he knows his onions when it come to X far better than I.

[Kevin Shea]

many thanks for the responses....for clarification, I downloaded the Xnest distribution from the X.org site and compiled it on an HP-UX 11 based workstation....checking the XServer configuration via SAM reveals the default visual is PseudoColor, Depth 8 and xdpyinfo reveals both X0 and X1 have depth of root window = 8 planes with (allowable) depths of 1,8,24. Also visual id's are set for PseudoColor (depth = 8 planes), Direct Color (depth = 24 planes) and TrueColor (depth=24 planes). The windows I am having trouble with are TrueColor (depth 24). In addition to the various Xnest options I cited in my original posting, I also (using sam) modified the XServer options to set the default visual to be TrueColor. After doing this the depth 24 windows display fine but some (but not all) depth 8 windows do not get displayed (but don't crash the Xserver!). Also I am launching Xnest by hand from and Xterm. Anyway ( as Chuck suggested) my plan was to next test with VNC, if I can't get Xnest to work. Was hoping to get Xnest working though, because it allows me to display stuff without loading software on the X client side. If you guys have any more suggestions would really appreciate the help.
Cheers, Kevin

[Kevin Shea]

Btw. I solved the problem of displaying remote applications that have either 8 bit or 24 bit depth windows using Xnest. I set my local X-server to Direct Color (using SAM) and this allows displaying windows with either depth ..and also my Xnest server doesn't crash which is a plus:)

[Charles Slivkoff]

Here's just a quick word of warning. I've seen appliations have problems with DirectColor visuals. Netscape 4.x , for example, is the one that comes to mind first. If the default visual is DirectColor, it will core on startup.