[Cosmic_announce] Re: Change in BUFR file header

[Doug Hunt]

Wilson:  OK, I'll fix it.  I was unsure about all those control codes...

Thanks,

   Doug

dhunt at ucar.edu
Software Engineer III
UCAR - COSMIC, Tel. (303) 497-2611

On Thu, 11 Jan 2007, Wilson.Fong at noaa.gov wrote:

> Doug,
>
> Your example below as show below is not correct:
>
> ####018008476####(0a0d0d0a)IUTJ..(ododoa)BUFR
>
> it should be just
>
> ####018008476####(0a)IUTJ...   (ododoa)BUFR
>
> The ####.....##### will be remove by out code.
>
> Wilson
>
>
> ----- Original Message -----
> From: Doug Hunt <dhunt at mail.cosmic.ucar.edu>
> Date: Thursday, January 11, 2007 6:18 pm
> Subject: Change in BUFR file header
>
>> Hi all:  In order to get cosmic BUFR files (bfrPrf) on the GTS, we
>> need to
>> make a small change to the header bytes at the beginning of the
>> bfrPrf
>> files.
>>
>> Currently, the header of a "WMO message" is being sent, which
>> starts
>> with:
>>
>> 00000000: 010d 0d0a 2d2d 2d0d 0d0a 4955 5446 3134  ....---...IUTF14
>> 00000010: 204b 5742 4320 3131 3030 3131 0d0d 0a42   KWBC 110011...B
>> 00000020: 5546 5200 2104 0300 0012 0000 3c00 0003  UFR.!.......<...
>>
>> In order to get the NESDIS DDS system to accept these files,
>> they need to have the WMO starting line:
>>
>> [SOH][cr][cr][lf]nnn  Where nnn is 0-999 sequence number
>>
>> replaced by a 'Flag Field Separator':
>>
>> ####018008476####[lf]
>>
>> where 018 is the flag field separator length and 008476 is the
>> BUFR
>> message length.
>>
>> So, the new files will start like this:
>>
>> 00000000: 2323 2323 3031 3830 3038 3437 3623 2323  ####018008476###
>> 00000010: 230a 0d0d 0a49 5554 4a31 3420 4b57 4243  #....IUTJ14 KWBC
>> 00000020: 2031 3032 3335 390d 0d0a 4255 4652 0021   102359...BUFR.!
>>
>> My understanding is that any good BUFR decoder will skip past
>> these initial bytes.
>>
>> The new files will have a 0001.0006_bufr suffix.  They will start
>> being
>> produced tomorrow.
>>
>> Regards,
>>
>>   Doug Hunt
>>
>> dhunt at ucar.edu
>> Software Engineer III
>> UCAR - COSMIC, Tel. (303) 497-2611
>>
>