Re: PROBLEM: blocking read on socket repeatedly returns EAGAIN

From: Alan Cox (alan_at_lxorguk.ukuu.org.uk)
Date: 08/16/05

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    To: Kern Sibbald <kern@sibbald.com>
Date:	Tue, 16 Aug 2005 15:03:11 +0100

    On Maw, 2005-08-16 at 15:19 +0200, Kern Sibbald wrote:
    > have written, nor does it write() anything. When my read() is issued, I
    > expect it to block, but it immediately returns with -1 and errno set to
    > EAGAIN. If the read() is re-issued, a CPU intensive loop results as long as
    > the other end does not read() the data written to the socket. This is a
    > multi-threaded program, but the other threads are all blocked on something.

    You are describing behaviour as expected with nonblocking set. That
    suggests to me that something or someone set or inherited the nonblock
    flag on that socket. Is the strange behaviour specific to the latest
    kernel ?

    Alan
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