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

Hi Jay-

> 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