[LDM #FMY-967366]: Core Dumps

Phil,

> Hopefully I am sending this to the right location.  I believe it is
> LDM related...

The problem probably isn't related to the LDM.  It's more likely
that the problem lies in the decoder that you're trying to run.

> I am trying to PIPE NEXRAD data to a program and have it A) store the
> file and B) Generate a gif image using GMAP.
> My problem is that I keep getting core dumps within the folder in
> which the script is located. (gempak/scripts/nexrad/) 

You'll need to determine the cause of the crashing.  Because LDM
decoders don't have a standard error stream, they must be written
so that they write any error messages to a log file.  The decoder
you're running doesn't appear to do that.

> Here's what I've noticed:
> 
> 1) This only happens occasionally, but is certainly related to
> creating to the NEXRAD script. When I disabled it, the core dumps
> stopped.
> 2) Reducing the number of radars did not seem to make much of a
> difference.
> 3)  I changed the script that stores the data from c shell to
> Perl... this seems to have reduced the frequency of the core dumps
> (down from 1 every 5 minutes to 4 over the past 8 hours). I would like
> to be able to execute gmap from Perl, but am not quite sure how to do
> that... I'll try and figure that out.
> 4) Could the dumps be because I am attempting to execute gpmap
> before the file has finished writing?

I don't know.  I'm not familiar with the "gpmap" utility.

> Any help is appreciated.  I have attached my entry from pqact as well
> as the Perl Script that stores the radar images and activates the c
> shell program.

Are there any relevant error messages in the LDM log file?

> --
> NEXRAD        ^SDUS[0-9]{2} .... (......) /p(...)(...)
> PIPE  -close   /usr/local/gempak/scripts/nexrad/nexrad.pl \3 \2 \1

Using the "-close" option is good.

> --
> #!/usr/bin/perl
> 
> # Get Variables from LDM
> $radarsite = $ARGV[0];
> $product = $ARGV[1];
> $prodtime = $ARGV[2];
> 
> $storefile = "/usr/local/ldm/data/nexrad/$radarsite/$product
> $prodtime.raw";

I'm not familiar with NEXRAD product-identifiers.  Is the pathname
pattern you're using sufficient to create unique files?

> open (FILEOUT, ">$storefile") or die "Could not open!";
> while(<STDIN>)
> {
> print FILEOUT $_;
> }

Reading until there's nothing left to read is good.

> close(FILEOUT);
> 
> 
> `/usr/local/gempak/scripts/nexrad/nexrad.csh $radarsite $product
> $prodtime`;

Which is crashing, the perl script or the "nexrad.csh" script?

> ----
> 
> Phil Birnie
> Webmaster
> Department of Geography
> The Ohio State University
> (614)519-6176
> www.birnies.com

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: FMY-967366
Department: Support LDM
Priority: Normal
Status: On Hold