Reading "leftover" chunks from files

[Matthew <I.Dont@Think.So>]

Greetings,

This is a "what's the best way of doing this" question.

I want to read in a file so that I can get fixed-length chunks of data
backwards, and also read in whatever data (smaller than the chunk size)
is left behind at the end of the file.

EG
If the file I'm reading is:

[ABC|DEF|GHI|JK] (where | represents a chunk border, not an actual byte)

I want to be able to read:
JK, then
GHI, then
DEF, then
ABC

I'd say Direct_IO comes into it, and the full-sized chunks (eg ABC) are
easy to get, but how do I pick up the JK without scanning through the
whole file?

MB
Email: ua.ten.qu@olokom (backwards)
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