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SubjectRe: Opening of blocking FIFOs not reliable?
Teemu wrote:

>Opening a FIFO for WR_ONLY should release a previously blocked RD_ONLY
>open. I suspect this is not guaranteed on a heavily loaded Linux box.
>
>
Do you have a test case?
IIRC we had that bug, and it was fixed by adding PIPE_WCOUNTER:
PIPE_WRITERS counts the number of writers. This one is decreased during
close(). PIPE_WCOUNTER counts how often a writer was seen. It's never
decreased. Readers that wait for a writer wait until PIPE_WCOUNTER
changes, they do not look at PIPE_WRITERS.

--
Manfred
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