You know, I was thinking that using PCRE with /fseek doesn't make too much sense... rather just finding the next offset that matches an exact string in the file would work just fine. But it must treat EOLs like any other character, and unless specified as part of the matching string, it continues seeking. Then load it into a &bvar where it can be further broken down.
Problem is, you can't perform regular expressions directly with binary variables.