On 05/05/2011 10:17 PM, Jeff Trawick wrote:
On Thu, May 5, 2011 at 3:20 PM, Eric van der Maarel
<[email protected]> wrote:
Hi,
Further investigation reveals a difference between running Tomcat on
Linux and Windows. From the Tomcat Poller thread the apr_pollset_poll()
is called. When a client in the pollset has disconnected, under Linux
this call returns (in the rtnevents member of the descriptors resultset)
49 (=0x31, so that would be APR_POLLIN | APR_POLLERR | APR_POLLHUP),
while under Windows this always return
1 (so APR_POLLIN)
The poller in Tomcat reacts on the APR_POLLHUP result, so differently on
Windows than on Linux. I think the problem lies in the missing
APR_POLLHUP in the poll return result under Windows (from the
impl_pollset_poll implemented in select.c by the way).
Anyone any idea why on Windows (select.c) the rtnevents does not have
the APR_POLLHUP flag up, while on Linux (no idea which poll provider
version is used ther :-) this flag is set when the client has disconnected?
And how to fix? :-)
select() has a simpler view of things; normally something needs to
read from the readable socket, get connreset or equiv, and handle
closed connection at that point
select() on any platform can't set APR_POLLHUP as a return event
maybe getsockopt(SOL_SOCKET/SO_ERROR) when socket is readable and
APR_POLLHUP was requested would give the necessary info????
Change the apr client you mean to handle receiving APR_POLLIN, right?
--/--
are you sure select() is being used? newer Windows should have WSApoll()?????
Yes, select() is being used (added some logging to select.c that
actually shows up). We're running on Windows XP (SP3) which, as I
understand it, doesn't have WSAPoll().
If XP does have WSAPoll(), how to enforce it? Is it determined buildtime
or runtime which poll/pollset provider is going to be used?
Can and should we use another provider than select on XP and how can
that be configured? Or, for this use case, shouldn't we use XP
altogether and use one of those server versions of Windows instead?
Eric
--
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| Eric van der Maarel |
| NEDAP IDEAS |
| [email protected] |
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