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[IDV #QHB-724761]: Question about "Making data source local" option.

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  • Subject: [IDV #QHB-724761]: Question about "Making data source local" option.
  • Date: Wed, 05 Aug 2009 16:08:45 -0600
Hi Jay-

Thanks to Tom Whittaker's help, I think I have a solution that sets the first 
word to 0 for ADDE images.  It will be in tomorrow's build.  Let me know if 
that solves your problem.   

Thanks to Dave for addressing the IMGLIST issue.

Don

> > A user in CIMSS and I have been trying out the "Making data source
> > local" option to create area files.  I've been using the latest IDV
> > nightly (from August 3rd), and the area files I'm producing are not
> > usable in the -V Local ADDE Manager or in -X.
> >
> > I've talked with TomW and DaveS and they've indicated the problem to
> > me... that a zero needs to be written into the first word of the area
> > file.  TomW mentioned that you had released a change on 1 July which
> > does this, and it was included in the last visad.jar file.  So, I'm
> > wondering if this change was lost, not implemented at the moment, or
> > broken, etc.  Here is the latest from TomW:
> 
> As you point out, the problem is that the first word is not 0.  There is 
> conflicting documentation on this.  If it's truly a bad image, why can one do 
> an IMGLIST on it?
> 
> That being the case, I have not yet implemented the change I made in 
> visad.jar in the IDV.  That requires some overhead which I'm not sure I want 
> to incur in the IDV. Currently, we just write the ADDE stream directly to 
> disk and the first word is not 0 in an ADDE Image object.  Using the VisAD 
> fix, I'd have to create an AreaFile out of each stream and then use the new 
> method to write to disk.  My attempts to just set word 0 after writing out 
> the ADDE stream fail on Windows because it locks the file and doesn't allow a 
> subsequent write.  It probably works on Linux, but I haven't had a chance to 
> test it there.
> 
> Dave Santek's workaround is to do an LWU POKE 0 0 on each file.  However, the 
> file names have to be short or you have to create links to each file with a 
> short name since LWU doesn't handle long names/paths.  But, that will work.
> 
> 


Ticket Details
===================
Ticket ID: QHB-724761
Department: Support IDV
Priority: Normal
Status: Open