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20000418: including AFOS header in ldm data stream

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  • Subject: 20000418: including AFOS header in ldm data stream
  • Date: Tue, 18 Apr 2000 15:38:02 -0600
Jeff,

The code to create the PIL id's was added to the LDM-5.0.9 distribution
from the wmo_header.c routine in pqing. The SSEC system injects 
the product into the LDM queue through pqing (which does all those 
FOS checks like cannonicalizing the wmo headers..such as WWUS9 to WWUS09).
If you are using pqing, then you will get the pils if you are using the
lastest version.

If you are creating the product names yourself for injecting directly
into the LDM queue from your software (as I do with my system)
then you will either want to cannonicallize your headers the same
way that wmo_header does (this includes the addition of the /m tags
for the grib products as well). The pil line should be recognized if
the line immediately following the WMO header is 5 or 6 characters-
all alphanumeric, but not all numbers. 

The SSEC ingestion code creates the FOS wrappers around the product
so that pqing recognizes the product as looking like a FOS and 
the decoders out there can find the start and end of the product.
I see that the SSEC product is 126 bytes and your is 111 bytes.
In FOS, all products were wrapped within:
SOH \r \r \n
# # #  \r \r \n
.....
\r \r \n ETX

The SSEC code makes the products backwards compatible with all the software 
out there that looks for those characters.

Steve Chiswell
Unidata User Support

>From: Jeff Masters <address@hidden>
>Organization: .
>Keywords: 200004182120.PAA27190

>
>   Hi, we have brought up some home-grown software to ingest the NOAAPORT
>FOS data on a Linux box and feed it to the ldm. We're not exactly sure,
>though, how to include the AFOS header like the U Wisconsin ingest box we
>have does. If we are going to be feeding the IDD, we need to get our Linux
>box sending out the AFOS headers, too.
>
>This is what the Wisconsin box sends out:
>
>Apr 18 15:54:36 pqutil:      126 20000418155459.526 IDS|DDPLUS 492  WWUS53
>KGID 181554 /pSVSGRI
>
>
>And here is what our Linux box sends out:
>Apr 18 15:54:32 pqutil:      111 20000418155432.532  DDPLUS 324  WWUS53
>KGID 181554
>
>Do you have any code/suggestions on how to emulate what the Wisconsin box
>sends out?
>
>Thanks,
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