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Date: Tue, 15 Apr 2014 18:18:30 +1000
Subject: Re: Python, Linux, and the setuid bit
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:70256

On Tue, Apr 15, 2014 at 6:15 PM, Chris Angelico <rosuav@gmail.com> wrote:
> then two's complement arithmetic will give the right result
> even if the discarded bits differ.

Clarification: Two's complement isn't the only way this could be done,
but it is the most likely. So, in theory, there are several possible
causes of disaster, but in practice, on any IBM PC compatible
architecture, casting a pointer to an integer will usually take the
lowest N bits, and two's complement arithmetic will be used, and the
environment is unlikely to hit 4GB in size, so the program will
"happen to work" in >99.999% of cases.

ChrisA