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----- Original Message -----
From: "Sergej R. Kosinskij" <ksr@xxxxxxx>
To: "mj.cava" <metastock@xxxxxxxxxxxxx>
Sent: Friday, May 18, 2001 3:05 PM
Subject: Re[4]: QP2 Directory limitation -- Janene
> Hello mj.cava,
>
> You are absolutely right but it is no mistake. Just look on formula, I
> have wrote, carefully. Today's date will be stored as 1010518.
> Here are first and last records extracted from a f*.dat file of the real
> database.
> F1.DAT
> 00000000: 00 00 44 04 00 00 00 00 ¦ 00 00 00 00 00 00 00 00
> 00000010: 00 00 00 00 00 00 00 00 ¦ 00 00 00 00 90 D7 6C 94
> 00000020: 37 89 41 7D A8 C6 4B 7D ¦ EE 7C 3F 7D A6 9B 44 7D
> 00000030: 00 95 76 98 00 00 00 00 ¦ A0 D7 6C 94 CB A1 45 7D
> ..........
> 00007730: AA D8 74 9A 33 B3 09 8B ¦ 30 B5 76 94 42 60 65 7D
> 00007740: 8B FD 65 7D F7 E4 61 7D ¦ AF 25 64 7D 10 D1 34 99
> 00007750: 66 96 0B 8B 40 B5 76 94 ¦ AE 47 61 7D AF 25 64 7D
> 00007760: 3F 35 5E 7D 40 13 61 7D ¦ 58 C9 5D 99 33 A3 08 8B
> 00007770: ¦
>
> The first record's date was stored as 90 D7 6C 94 = 970105
> The last record's date was stored as 40 B5 76 94 = 1010516
QED.
That's the way the ancient Equis/Computrac (YYMMDD) format was modified in
Q4 1998 to support dates outside (19)00-(19)99.
The original format was not Y2K compatible.
The Equis Metastock Y2K compatible format (ie 6.51+) does write CYYMMDD
floating point values, where C=0 when century=19, C=1 when century=20, etc.
> Here are the Downloader explanations:
> 01/05/1997 0.09450 0.09950 0.09350 0.09600 16160000 0
> ...........
> 05/16/2001 0.11000 0.11140 0.10850 0.10990 29070000 1093
>
> Also look into a master file especially on 4 starting bytes. There are
> a total number of the f*.dat files and highest number of the f*.dat.
> Both numbers occupies 16 bits.
YES... but (see below)
> MASTER
> 00000000: 05 00 05 00 00 00 00 00 ¦ 00 00 00 00 00 00 00 00
> 00000010: 00 00 00 00 00 00 00 00 ¦ 00 00 00 00 00 00 00 00
> 00000020: 00 00 00 00 00 00 00 00 ¦ 00 00 00 00 00 00 00 00
> 00000030: 00 13 6F 6E 81 01 65 00 ¦ 1C 07 00 00 42 72 69 74
The (E)MASTER files contain 1 header record and up to 255 master security
information records.
The dump you provided above is the 1 header record.
In all other (E)MASTER records, the security f*.dat number is stored in a 8
bits (unsigned character) field.
Conclusion : the old Equis/Computrac format was not ready to receive more
than 255 symbols per directory either.
Alain
__________________________
> mc> Sorry Sergej, methink you are wrong :
> mc> 1) The old database format (Equis/Computrac) is NOT Y2K compatible.
> mc> Century=19 was assumed. Dates were saved as YYMMDD floating point
values.
> mc> 2) The old emaster and master files do use 8 bits (unsigned character)
to
> mc> store the security 'nnn' number (of Fnnn.dat)
>
>
> /ksr
> mailto:ksr@xxxxxxx
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