Re: Odd IFS reading issue

[Charles Wilt <charles.wilt@xxxxxxxxx>]

Aaron,

Isn't the part you're highlighting in your screen caps the bytes 1025-1029?

Since 1024 is evenly divisible by 16, I'd expect the 1024th byte to be
the last byte of the row above.

Charles

On Thu, Jul 2, 2009 at 11:43 AM, Aaron Bartell<aaronbartell@xxxxxxxxx> wrote:
>   I have an IFS file reading issue that I can't quite figure out.  The
>   general idea is that I want to incorporate a process of streaming an IFS
>   file from one place to the next in chunks of 1024 vs. reading it with a
>   single call to read() after first allocating space based on the file size.
>
>   The scenario is as follows:  I have a file named small.jpg in the IFS that
>   is 1067 bytes in size.  When I read in 1024 bytes the 1024th byte is
>   different than when I read in all 1067 bytes at a time.  The 1024th byte
>   when I read 1024 at a time is x'AF' (which appears as the Registered
>   symbol) and the 1024th byte when I read in the entire file of 1067 bytes
>   is x'94' (a lower case letter m).  Crazy eh?
>
>   Here are some screen shots of the memory differences (highlighted) in
>   WDSC's Memory view:
>   [1]http://mowyourlawn.com/temp/readbyteissue_dataptr1.png
>   [2]http://mowyourlawn.com/temp/readbyteissue_dataptr2.png
>
>   Here is the concise program I put together to test the issue:
>   [3]http://mowyourlawn.com/temp/READBYTE.RPGLE
>
>   Here is the small.jpg file I am using in the test.
>   [4]http://mowyourlawn.com/temp/small.jpg
>
>   Anybody have any ideas of what might be going on?  Am I missing something
>   stupid?
>
>   Aaron Bartell
>   [5]http://mowyourlawn.com
>
> References
>
>   Visible links
>   1. http://mowyourlawn.com/temp/readbyteissue_dataptr1.png
>   2. http://mowyourlawn.com/temp/readbyteissue_dataptr2.png
>   3. http://mowyourlawn.com/temp/READBYTE.RPGLE
>   4. http://mowyourlawn.com/temp/small.jpg
>   5. http://mowyourlawn.com/
> --
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