Message 168529 - Python tracker

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In-reply-to
Author	pitrou
Recipients	bsdphk, pitrou
Date	2012年08月18日.20:22:37
SpamBayes Score	-1.0
Marked as misclassified	Yes
Message-id	<1345321358.42.0.438325373197.issue15723@psf.upfronthosting.co.za>

Content
> When a file is opened in append mode, the operating system guarantees > that all write(2) system calls atomically appended their payload to the > file. Does it? I don't see such strong guarantees in http://pubs.opengroup.org/onlinepubs/9699919799/functions/write.html In any case, Python 2 uses fwrite() not write(), so it may be the explanation. Do you observe the same behaviour when using io.open() instead of open()? (io.open() is the Python 3 IO stack backported to Python 2)

Content

> When a file is opened in append mode, the operating system guarantees
> that all write(2) system calls atomically appended their payload to the 
> file.
Does it? I don't see such strong guarantees in http://pubs.opengroup.org/onlinepubs/9699919799/functions/write.html
In any case, Python 2 uses fwrite() not write(), so it may be the explanation. Do you observe the same behaviour when using io.open() instead of open()?
(io.open() is the Python 3 IO stack backported to Python 2)

History
Date	User	Action	Args
2012年08月18日 20:22:38	pitrou	set	recipients: + pitrou, bsdphk
2012年08月18日 20:22:38	pitrou	set	messageid: <1345321358.42.0.438325373197.issue15723@psf.upfronthosting.co.za>
2012年08月18日 20:22:37	pitrou	link	issue15723 messages
2012年08月18日 20:22:37	pitrou	create

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