Based on my understanding on your post.
You have the algorithm on hand.
Does this trailer also has header?, if so it is very easy. it fits into your existing algorithm.
If it doesn't have header don't worry, after reading all the records based on the length of the records(first 4 bytes at the start of every record), only the trailer is going to be remaining take it off easily.
if you worry that while reading the records if are about to mistakenly read the trailer, then you have a problem.
for that you maintain a counter and store the size of the entire set of records(including trailer), and after reading every record just subtract the current length of the record in the existing counter(+4). if you have only 40 remaining on the counter; skip the remaining bytes.
You missed to tell us that; where you are reading this record from, either from file/socket/pipe .. etc?.
Vivek
-- In accordance with the prarabdha of each, the One whose function it is to ordain makes each to act. What will not happen will never happen, whatever effort one may put forth. And what will happen will not fail to happen, however much one may seek to prevent it. This is certain. The part of wisdom therefore is to stay quiet.

In reply to Re: How to capture data length from the record ? by targetsmart
in thread How to capture data length from the record ? by bh_perl

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