Re: WaitLatch

On Mon, Dec 13, 2010 at 5:48 AM, aaliya zarrin <aaliya(dot)zarrin(at)gmail(dot)com> wrote:
> drainSelfPipe() function will read the data and remove it from the
> descriptor?

Yes...

> Coz the signal (SIGUSR1) is writing sata to selfPipe descriptor but unable
> to wake up latch on select system call.

The signal won't cause the select() to return, but the byte that the
signal handler writes to the self-pipe ought to make it return.

> Data is not avaialable at select in WaitLatch fun. Coz it is read by
> drailSelfPipe().

I'm not sure what you're talking about here. drainSelfPipe() is
called before calling SELECT. As soon as a self-pipe byte is written,
the SELECT will return.

--
Robert Haas
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