If you are only discarding from the first (double) record, then if the original file is sync'd, the resultant file will be: 

Read 
|------------|------------|------------|------------|---|
---------------------------------------------------------
....|s 7680 bits |s 7680 bits |s 7680 bits |s 7680 bits |
---------------------------------------------------------
write
<<<<|s-------|----s-------|----s-------|----s-------|---|
|s-------|----s-------|----s-------|----s-------|---|
-----------------------------------------------------
|s 7680 bits |s 7680 bits |s 7680 bits |s 7680 bits |
-----------------------------------------------------

[download]

Anyway, good luck.

Examine what is said, not who speaks.
Silence betokens consent.
Love the truth but pardon error.

In reply to Re^15: pack/unpack binary editing by BrowserUk
in thread pack/unpack binary editing by tperdue

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