Dave's implementation removes the EMWIN header (I hope). However, I was
swamped yesterday and I tasked this one out. I didn't test it. If
there's an issue, it's mine.
Stripping extraneous linefeeds is pretty trivial. There's nothing to
prevent doing that and then doing a pqinsert, if we have to.
And... I understand the issues of working with the TOC and the
constraints they have to work under.
gc
daryl herzmann wrote:
On Thu, 16 Dec 2010, Gerry Creager wrote:
I'll try to figure out what we did wrong here. We're snagging the same
EMWIN feed Gilbert is, but could have fumble-fingered something, since
I'm still short of calibrated fingers since shoulder surgery...
Unfortunately, one can not seamlessly plex together the
EMWIN/WeatherWire with the NOAAPORT/SBN dataset using baseline
software. I forget which system does it, but one of them arbitrarily
tacks on an extra DOS line feed to every product, thus LDM sees the same
product twice, since the line feeds are used to compute the product
checksums.
For NWSChat, I get a direct socket feed from the Gateway/TOC that
contains the plexing of, I think, 4 different internal NWS systems.
This feed has duplicates all day long. So when Gilbert was hoping for a
direct backup IDD feed from the TOC, this problem would have caused lots
of pain for others... Anyway, I ended up writing a pre-conditioner to
my decoders that striped extraneous line feeds and computed product
checksums that way. This works for 99% of the products, but there are a
few more products that have extra control characters inserted (namely
from SPC) into the non SBN feeds.
My impression is that the private sector weather folks have been dealing
with this issue for a very long time and it has been frustrating for
them. I've been bugging the TOC/Gateway folks about it, but they are
extremely short of resources and dealing with ancient IBM computer
systems. This issue is on their TODO list though.
I wish LDM had an option to arbitrarily strip trailing line feeds before
checksum computation. Before somebody says this would be a performance
killer, it isn't. :)
daryl
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Gerry Creager -- gerry.creager@xxxxxxxx
Texas Mesonet -- AATLT, Texas A&M University
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