Re: Python, Linux, and the setuid bit

References	<mailman.9260.1397511440.18130.python-list@python.org> <wwv7g6rqax4.fsf@l1AntVDjLrnP7Td3DQJ8ynzIq3lJMueXf87AxnpFoA.invalid> <CAPTjJmrDb5YFi094ZSQXV=Vz1QnBQJNbWUMc309QTpNVPQNUaA@mail.gmail.com>
Date	2014-04-15 18:18 +1000
Subject	Re: Python, Linux, and the setuid bit
From	Chris Angelico <rosuav@gmail.com>
Newsgroups	comp.lang.python
Message-ID	<mailman.9273.1397549919.18130.python-list@python.org> (permalink)

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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

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Python, Linux, and the setuid bit Ethan Furman <ethan@stoneleaf.us> - 2014-04-14 14:13 -0700
  Re: Python, Linux, and the setuid bit John Gordon <gordon@panix.com> - 2014-04-14 21:55 +0000
    Re: Python, Linux, and the setuid bit Grant Edwards <invalid@invalid.invalid> - 2014-04-14 22:04 +0000
      Re: Python, Linux, and the setuid bit Grant Edwards <invalid@invalid.invalid> - 2014-04-14 22:07 +0000
  Re: Python, Linux, and the setuid bit Richard Kettlewell <rjk@greenend.org.uk> - 2014-04-15 09:00 +0100
    Re: Python, Linux, and the setuid bit Chris Angelico <rosuav@gmail.com> - 2014-04-15 18:15 +1000
      Re: Python, Linux, and the setuid bit Richard Kettlewell <rjk@greenend.org.uk> - 2014-04-15 10:28 +0100
        Re: Python, Linux, and the setuid bit Chris Angelico <rosuav@gmail.com> - 2014-04-15 19:35 +1000
    Re: Python, Linux, and the setuid bit Chris Angelico <rosuav@gmail.com> - 2014-04-15 18:18 +1000

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