I now have the decompression script running, stripping off all unused headers, and able to be PIPE'd into from pqact.conf. The resulting file that is written to disk looks identical to those currently broadcast using the WSI data feed type to those who subscribe to it.
Here's the lowdown. Remember the tabs between pieces here will likely show up as spaces in this document.
You need to have the zlib libraries installed on your system. Most linux boxes already have them, but others may need to install from source (http://www.info-zip.org/pub/infozip/zlib/)
You need to have perl installed somewhere on your system, and you need to install (if it's not already) the perl interface to zlib, also available from the above zlib web site.
Then call the nids_inflate.pl script from pqact.conf. Make sure you change the path on that line to point to where your perl lives.
My ldmd.conf REQUEST line looks like:
request HDS "^SDUS53 KARX.*" sunset.meteor.wisc.edu
I'm only pulling in the radar portion of the HDS stream to this particular machine, not the whole enchilada of HDS.
My pqact.conf line for this radar data looks like:
HRS ^SDUS53 K(ARX) (..)(....) /p(...).*
PIPE
-close /usr/local/ldm/util/nids_inflate.pl /usr/local/ldm/data/nids/\1/(\2:yy)(\2:mm)\2\3.\1.\4
This results in the following type file name being created
/usr/local/ldm/data/nids/ARX/0011DDHHMM.TTTwhere:
The whole string after 'nids_inflate.pl' is just an argument to the script, which is the file name that the data gets written to, so you can change that to suit your needs.
I have developed and tested this under RedHat linux 6.1/6.2, so your mileage may vary on other platforms, but perl is pretty platform independent, so there shouldn't be any issues.
Performance-wise, I don't see any hit at all, it runs so fast, but that's just a few products from one station. I would imagine sending all 108 or whatever radars and a full suite of products might cause it to be more of an issue.
One other thing, the WSI data seems to come out with the time rounded to the nearest 5 minutes, whereas the IDD NIDS data does not. This was only an issue for me, because I had wxp's rad command looking for files with the time rounded to 5 minutes - something like
nids-ARX %D/ARX/%y%m%d%h%5n.ARX.%e
in the ~wxp/etc/ymdh file.
Since many of the file names are not rounded to the nearest 5 minutes, it didn't find them, even when you'd specify the correct file name/time.
I changed that to read:
nids-ARX %D/ARX/%y%m%d%h%1n.ARX.%eand all is well.
Good luck, hope this helps everyone out, feel free to email me with questions, problems, successes, etc.
Pete Pokrandt
poker@meteor.wisc.edu