[IDV #QJR-730252]: ISL: Close an IDV display window after capturing an image, or better, dispense with a display window altogether

> Yuan,
> 
> I have a little bit of new insight into the problem of running the IDV 
> headlessly on a Mac.
> 
> First, I discovered that I had several problems with the X11 forwarding 
> configuration both on my Web server, virga.sfsu.edu <http://virga.sfsu.edu/> 
> (where I do my IDV bundle and ISL script development for the Web server) and 
> on my laptop at home (from which I log onto virga, which is 200 miles away). 
> I solved those problems by reinstalling XQuartz on both machines, specifying 
> in /etc/ssh/ssh_config on both machines a path to auth (which is included 
> with XQuartz), and making sure that X11 forwarding was enabled on both 
> machines. X11 forwarding now works as I expect it to.
> 
> Second, once that problem was fixed, I then discovered that I could run any 
> program that uses X-windows for graphical output in headless mode on virga. 
> As outlined by Suvy in his 2015 email contribution in the idvuser email 
> archives, I can set the DISPLAY variable from the command line or in scripts, 
> together with Xvfb (which is installed with XQuartz), run either from the 
> command line or in scripts, and entered either directly into a Mac Terminal 
> or XQuartz xterm window on virga via a VNC connection from my laptop (which 
> controls the remote screen on virga) or via an ssh connection to virga from 
> my laptop, and run programs that rely on X-windows for graphical display, in 
> headless mode.
> 
> For example, WXP (Dan Vietor’s weather graphics package from the 1990s and 
> early 2000s) uses X-Windows for graphical display, and virga runs WXP 
> programs to create GIF imagery, both on cron schedules and triggered by the 
> LDM. Until today those programs required that a monitor be attached to virga 
> and that XQuartz be running continuously so that the WXP programs could open 
> an X-window, create a display, and save the display as a GIF image. However, 
> I’ve now reconfigured these programs to run headlessly, essentially as 
> follows:
> 
> export DISPLAY=:DISPLAY#  (Example of a DISPLAY#:  :99)
> Xvfb :DISPLAY# &
> export DISPLAY=:DISPLAY#
> Run any WXP program that generates GIF images
> 
> This works successfully, and I no longer have X-windows popping up all the 
> time on virga when I’m trying to do something else there via a VNC 
> connection, a real annoyance.
> 
> Unfortunately, the IDV on a Mac does not rely on X-windows to create 
> graphical displays, so none of this makes a whit of difference. As one 
> pie-in-the-sky solution, Is it possible to tell the IDV to address its 
> graphical output to an X-window on a Mac? That might solve the problem. (I 
> wouldn’t want to installer a virtual LINUX operating system on my Mac and run 
> the IDV from within it, though!)
> 
> Second, on another front, I tried adding "-Djava.awt.headless=true” to the 
> java command line run by the runIDV script. The IDV java command then looks 
> like this:
> 
> /Applications/IDV/jre.bundle/Contents/Home/jre/bin/java 
> -Djava.awt.headless=true 
> -Djava.ext.dirs=/Applications/IDV/jre.bundle/Contents/Home/jre/lib/ext/ 
> -Xdock:name=IDV -Xmx3072m  -XX:+DisableExplicitGC -Didv.enableStereo=false 
> -jar /Applications/IDV/idv.jar
> 
> Running this command produces the following Java error messages:
> 
> ERROR: Fatal error initializing resources
> java.awt.HeadlessException
> Exception in thread "main" java.awt.HeadlessException
> at java.awt.GraphicsEnvironment.checkHeadless(GraphicsEnvironment.java:207)
> at java.awt.Window.<init>(Window.java:536)
> at java.awt.Frame.<init>(Frame.java:420)
> at java.awt.Frame.<init>(Frame.java:385)
> at 
> javax.swing.SwingUtilities$SharedOwnerFrame.<init>(SwingUtilities.java:1758)
> at javax.swing.SwingUtilities.getSharedOwnerFrame(SwingUtilities.java:1833)
> at javax.swing.JDialog.<init>(JDialog.java:272)
> at ucar.unidata.util.GuiUtils.createDialog(GuiUtils.java:2281)
> at ucar.unidata.util.LogUtil.printException(LogUtil.java:913)
> at ucar.unidata.util.LogUtil.printException(LogUtil.java:822)
> at 
> ucar.unidata.idv.IntegratedDataViewer.logException(IntegratedDataViewer.java:3063)
> at ucar.unidata.idv.IntegratedDataViewer.<init>(IntegratedDataViewer.java:309)
> at ucar.unidata.idv.IntegratedDataViewer.<init>(IntegratedDataViewer.java:224)
> at ucar.unidata.idv.DefaultIdv.<init>(DefaultIdv.java:69)
> at ucar.unidata.idv.DefaultIdv.main(DefaultIdv.java:150)
> 
> — Dave
> 
> ***************************************************************
> * Dr. Dave Dempsey, Prof. Emeritus  |       ^    ___    \|/   *
> * Dept. of Earth & Climate Sciences |  )   ^   /||_||\ —-0—-  *
> * San Francisco State University    | )  )    / ||_|| \ /|\   *
> * 1600 Holloway Ave.                |  )  )  /  ||_||  \      *
> * San Francisco, CA   94132         |  )  ) /   ||_||   \  ^  *
> *                                   | )  )  )   ||_||    \    *
> * Cell:   (415) 802-5548            |  )  )  )~~||~||~~~~~\~~ *
> * Email:  address@hidden          | )  )  )  ) ~  ~ ~ ~ ~ ~ *
> ***************************************************************
> 
> > On Apr 17, 2020, at 11:10 AM, Unidata IDV Support <address@hidden> wrote:
> >
Well, I really have no idea how to help, you get more knowledge in this area. 
The only thing I can tell is that your choice of adding headless
in the runIDV script is not a good idea and it will not work.

let me know if you eventually get the solution and it will benefit other IDV 
users.

Yuan

Ticket Details
===================
Ticket ID: QJR-730252
Department: Support IDV
Priority: Normal
Status: Open
===================
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