Python: slicing a very large binary file

Posted by Duncan Tait on Stack Overflow See other posts from Stack Overflow or by Duncan Tait
Published on 2010-03-02T13:47:17Z Indexed on 2010/03/19 15:51 UTC
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python

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binary

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large-files

Say I have a binary file of 12GB and I want to slice 8GB out of the middle of it. I know the position indices I want to cut between.

How do I do this? Obviously 12GB won't fit into memory, that's fine, but 8GB won't either... Which I thought was fine, but it appears binary doesn't seem to like it if you do it in chunks! I was appending 10MB at a time to a new binary file and there are discontinuities on the edges of each 10MB chunk in the new file.

Is there a Pythonic way of doing this easily?

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