As I replied to fglock I can't change the files structure, only it's data. i.e. I can add/remove/change lines but I have no control over "how" they're represented.

Each line is a fixed length record in itself, but each record type has a different structure. Say, a "print here" may be: 

x pos (6 char) y pos (6 char) string (300 char)

[download]

and a "new sheet" may be

sheet number (4 char) stock code (10 char)

[download]

and so on (those aren't real structures above but similar to the real thing).

I was toying with the idea of creating index files, but that comes with the overhead of having to parse the original file first to create them (if I could do that quickly it wouldn't be so much of a problem ;-)).

--- Jay

All code is untested unless otherwise stated.
All opinions expressed are my own and are intended as guidance, not gospel; please treat what I say as such and as Abigail said Think for yourself.
If in doubt ask.

In reply to Re^2: How to get fast random access to a large file? by gothic_mallard
in thread How to get fast random access to a large file? by gothic_mallard

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