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Date: Thu, 2 Jul 2015 05:28:36 +1000
Subject: Re: Python 3 resuma a file download
From: Chris Angelico <rosuav@gmail.com>
Cc: "python-list@python.org" <python-list@python.org>
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Xref: csiph.com comp.lang.python:93385

On Thu, Jul 2, 2015 at 5:24 AM,  <zljubisic@gmail.com> wrote:
>     with urllib.request.urlopen(req) as response, open(lfile, 'ab') as out_file:
>         data = response.read() # a `bytes` object
>         out_file.write(data)
>

If a file is big enough to want to resume the download once, you
almost certainly want to be able to resume it a second time. I would
recommend not attempting to do the entire read and write as a single
operation - read chunks and write them to the disk. This will attempt
to read the entire response into a gigantic in-memory bytestring, and
only then start writing.

ChrisA