Message 8/569  From Jeroen van der Zijp             Apr 27, 05 12:26:43 PM -0500
Organization: FOX Toolkit
To: foxgui-users@lists.sourceforge.net
Subject: Re: [Foxgui-users]fox issues between xwindows / windows.
Cc: Abe Stephens <abe@sci.utah.edu
RJLRef: $PH/COOL-BDE/foxXWindowsDebugging.hlp

On Wednesday 27 April 2005 03:46 am, Abe Stephens wrote:
> Hey,,
>
> I've had some difficultly running a fox application remotely using
> xwindows. I've tried this on several different machines with different
> builds of fox, so I think there is a possibility I am doing something
> that I shouldn't be.
>
> I have an application which displays an image to the user with an
> FXImage/FXImageView. This image is refreshed when the user presses a
> key, if the user presses a key rapidly, the application dies with the x
> errors listed below. On a key stroke, several other threads go out and
> refresh a copy of the image, which is then copied into the FXImage's
> data by the gui thread.
>
> Displaying on a linux prism from a linux altix: (fox 1.4 built on Intelicpc, ia64)
> X Error: code 16 major 41 minor 0: BadLength (poly request too large or
> internal Xlib length error).
>
> Displaying on a linux prism from an origin (fox  1.4 built on MipsPro)
> X Error: code 14 major 1 minor 0: BadIDChoice (invalid resource ID
> chosen for this connection).
> X Error: code 1 major 0 minor 0: BadRequest (invalid request code or no
> such operation).
>
> Displaying on an origin from one of the origin's heads (fox  1.4 built on MipsPro)
> X Error: code 16 major 3 minor 0: BadLength (poly request too large or
> internal Xlib length error).
>
> Here is basically what the code looks like.. I have an FXImage:
>
> // In the constructor:
> fx_image = new FXImage( getApp(), fx_image_data, IMAGE_KEEP, width,
> height );
>
> After updating the data of the fx_image, I call
>
> // Copy stuff into fx_image_data...
>
> fx_image->render();            // FXImage *
> fx_image_frame->update(); // FXImageView *
>
> Everything works wonderfully on a windows xp xeon build of the same
> software, of course theres no x server involved on that machine. The
> errors only occurs if I press keys rapidly which cause the software to
> refresh the image.
>
> I'm not an X-windows programmer (one reason I enjoy fox) so any
> suggestions would be helpful--

Its very strange because it seems to me that the request codes
don't have any bearing on generating X11 images...


What I recommend is to (1) pass the "-sync" argument when you're
starting your application, and (2) put a breakpoint in the xerrorhandler.

This will allow you to see what actual X11 command caused the trouble.

Without the "-sync" the commands are buffered which means that the error
code is not necessarily correlated with the last command issued from the
client.

Hope this helps,
        Jeroen