On Mon, Dec 13, 2010 at 5:48 AM, aaliya zarrin <aaliya.zarrin@gmail.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
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company
