Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!eu.feeder.erje.net!eternal-september.org!feeder.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail
From: Marko Rauhamaa <marko@pacujo.net>
Newsgroups: comp.lang.python
Subject: Re: open() and EOFError
Date: Mon, 07 Jul 2014 19:08:46 +0300
Organization: A noiseless patient Spider
Lines: 27
Message-ID: <87a98lb181.fsf@elektro.pacujo.net>
References: <53ba11fc$0$29985$c3e8da3$5496439d@news.astraweb.com> <c1uo2eF60gfU1@mid.individual.net> <53ba538d$0$2926$c3e8da3$76491128@news.astraweb.com> <mailman.11587.1404735570.18130.python-list@python.org> <53bac097$0$29995$c3e8da3$5496439d@news.astraweb.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Injection-Info: mx05.eternal-september.org; posting-host="ff5cf27ef3d5b31f034d3b72bdc27a41"; logging-data="17767"; mail-complaints-to="abuse@eternal-september.org";	posting-account="U2FsdGVkX1+je/v31YelYdI8zmJlpuMK"
User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.3 (gnu/linux)
Cancel-Lock: sha1:woIYISBR3Y9kDs+NONaxVpqYga8= sha1:D9Y48enjvmlU1QAXzWH9dwwlATw=
Xref: csiph.com comp.lang.python:74121

Steven D'Aprano <steve+comp.lang.python@pearwood.info>:

> On Mon, 07 Jul 2014 22:19:20 +1000, Chris Angelico wrote:
>
>> It's possible for input() to raise IOError, if I'm not mistaken;
>> consider redirection, for instance.
>
> What indirection? Do you mean, if built-in input() has been monkey-
> patched? Well, sure, but in that case it could do anything. I'm only
> concerned with the builtins. Otherwise, I have no idea what you mean
> by that.

input() quite naturally can raise an IOError. For example:

    import os, socket
    s = socket.socket(socket.AF_UNIX)
    s.bind("xyz")
    os.dup2(s.fileno(), 0); print(input())

results in an IOError (EINVAL, to be exact).

strace reveals that input() simply delegates to:

  read(0, 0xb73aa000, 4096)               = -1 EINVAL (Invalid argument)


Marko