Trying to understand file streaming, i'm
using POLs, CFile class, which is basically
a thin wrapper over the streaming api.

My usage of these calls is very basic, i first
do a call like:

Open(0,"MyFile",'MYID','DATA',fileModeReadWrite);  (FileOpen)

..then i read serial data in an event handler and write it out:
Write(pData,nCount); (FileWrite)

..and when i'm done, i close the file:
Close(); (FileClose)

...seems simple, and it does create a file, but not what
i expected. My test created a 51k pdb file. I thought a streaming
PDB would be one large record chunk of pure data, but that is
not the case. It created 13 records of 4k (4096 bytes) each and
there was some overhead data in each record.

The 1st record looked like:

'D','B','L','K',0x00,0x00,0x10,0x00, 16 bytes date stamp, then
my user data

Subsequent records looked like this:

2nd record:
user data,'D','B','L','K',0x00,0x00,0x10,0x00,user data,...

3rd record:
user data,user data,'D','B','L','K',0x00,0x00,0x10,0x00,user data,...

4th record:
user data,user data,user data,'D','B','L','K',0x00,0x00,0x10,0x00,user
data,...

..the odd part is "'D','B','L','K',0x00,0x00,0x10,0x00" shows up in
each record and increases the offset in each subsequent record by 1.
This is how my conduit reads the record (i also used PDBingo and eyeballed
the hex file to check this is how data is stored and thats what i see)
...is this correct ? ...i can parse out this overhead, but looks to
be more of a pain then i thought it would be. ..thanks



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