Re: [Swarm-Support] Problem with HeatBug example under cygwin and Swarm-2.2-java

[Bill Northcott]

> However, when not in batch mode, I can not see the main window with  
> the
> start and stop buttons and I got the following error:
>
> error: TkExtra (instance)
This error is actually in the MacOS X FAQ but not Windows.

It can occur on any system that does not use X11 for its default  
display, which in practice means MacOS or Windows.

The cause is very simple.  The X11 server must be running before you  
attempt to launch Tk or it crashes with that message.  You will get  
the same error by typing 'wish' at the Cygwin prompt.

The cure is equally simple:  Start the X11 server before attempting  
to start a GUI Swarm app.

Bill Northcott