Point 1: This is variable data, not fixed.

Point 2:

How about something like:
open file;
$Header_length = 2;
while(sysread (file, $data, $Header_length)){
$mask = 'xyz';
$body_length = unpack $mask $data;

sysread (file, $data, $body_length);
$mask= 'MNO';
$body=unpack $mask $data;
...
}

In reply to Re: Unpacking fixed length records by Anonymous Monk
in thread Unpacking fixed length records by diotalevi

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