[Twisted-Python] Re: plus mode was Re: how winnt fileops workandwhat to do about it

Paul G paul-lists at perforge.com
Sat Dec 31 18:56:49 EST 2005


----- Original Message ----- 
From: "Jean-Paul Calderone" <exarkun at divmod.com>
To: "Twisted general discussion" <twisted-python at twistedmatrix.com>
Sent: Saturday, December 31, 2005 6:46 PM
Subject: Re: [Twisted-Python] Re: plus mode was Re: how winnt fileops 
workandwhat to do about it


> On Sat, 31 Dec 2005 18:12:06 -0500, James Y Knight <foom at fuhm.net> wrote:
>>
>>On Dec 31, 2005, at 4:57 PM, Paul G wrote:
>>>oh, it makes perfect sense to have a workaround in twisted, i'm not 
>>>suggesting otherwise. however, it should be just that - a temporary 
>>>workaround until cpython has a fix for the issue, because (outside  of 
>>>the offending libc implementation), that is the right place to  fix it.
>>
>>As I wrote in the bug report:
>>>It's not a python bug except perhaps that python should raise an 
>>>exception.
>>>Doing a read and write without a seek in between is illegal in C.
>>>
>>>"ANSI C requires that a file positioning function intervene between 
>>>output and
>>>input, unless an input operation encounters end-of-file."
>>
>>I am against including any sort of workaround besides raising an 
>>exception if the situation occurs. And I don't think even that is 
>>particularly warranted.
>
> Thanks for pointing this out.  The immediate fix is now obvious: the test 
> needs to change.  It _might_ be nice to have an assertion for this 
> behavior, but I'm not about to add a file wrapper just for this (if all of 
> Twisted used FilePath, instead of opening files directly, I might grant 
> more weight to this, but since it doesn't...).

are we sure streams are only used with File objects FilePath gives us?

-p





More information about the Twisted-Python mailing list