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Message-ID: <3DADC5F8.60708@kegel.com>
Date: Wed, 16 Oct 2002 13:03:04 -0700
From: Dan Kegel <dank@kegel.com>
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To: John Gardiner Myers <jgmyers@netscape.com>
CC: Davide Libenzi <davidel@xmailserver.org>,
       Benjamin LaHaise <bcrl@redhat.com>,
       Shailabh Nagar <nagar@watson.ibm.com>,
       linux-kernel <linux-kernel@vger.kernel.org>,
       linux-aio <linux-aio@kvack.org>, Andrew Morton <akpm@digeo.com>,
       David Miller <davem@redhat.com>,
       Linus Torvalds <torvalds@transmeta.com>,
       Stephen Tweedie <sct@redhat.com>
Subject: Re: [PATCH] async poll for 2.5
References: <Pine.LNX.4.44.0210151403370.1554-100000@blue1.dev.mcafeelabs.com> <3DAC9035.2010208@netscape.com>
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John Gardiner Myers wrote:
>>     while (read() == EAGAIN)
>>         wait(POLLIN);
>>
> Assuming registration of interest is inside wait(), this has a race.  If 
> the file becomes readable between the time that read() returns and the 
> time that wait() can register interest, the connection will hang.

Shouldn't the should be rearmed inside read() when it returns EAGAIN?
That's how I do it in my wrapper library these days.
No reason to have a race.

- Dan

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