Re: need help with perl-ldap 0.24 on NT over Cygwin

[Graham B. <gb...@po...>]

On Wed, Aug 01, 2001 at 06:29:53PM +0100, Chris Ridd wrote:
> Graham Barr <gb...@po...> wrote:
> > Thats interesting to note.
> > 
> > However what is happening in this case is that select is stating it is
> > ready for reading, but the first sysread after that is returning zero.
> > 
> > That normally means the server has closed the connection. But I find it
> > strange that it would do that without first responding to the bind
> > request.
> > 
> > Graham.
> 
> Hm, we have observed select behaving oddly on different versions of Windows
> here.
> 
> The problem we had was that we were calling WSAEventSelect after we got a
> success from WSAWaitForMultipleEvents. On some versions of Winsock (like in
> '95, and NT with SP 4 or higher) this doesn't work because the event code
> is edge triggered, whereas previous SPs were edge triggered. In other
> words, the behaviour post SP4 was that 'I told you about the socket once, I
> won't tell you again.'
> 
> So if sysread is checking for events itself, this might explain the problem.
> 
> I wouldn't be at all surprised if things like Cygwin modified how perl's
> I/O worked.
> 
> Could this therefore be a problem in the NT port of perl?

I cannot really answer that as I know little about NT. So this really
needs to be put before the win32 people on perl5-porters.

If anyone knows how to reliably reproduce the problem, I suggest they sent
a description to per...@pe...

Graham.