[Libevent-users] libevent win32 issues

[Toby Douglass]

Nick Mathewson wrote:
> On Tue, Nov 06, 2007 at 05:09:07PM +0100, Marc Lehmann wrote:

> There are two factors that keep the select() implementation on win32
> from using the same strategy/code as the one :
>
>    1) win32's select() doesn't use bitfields; it uses an array of
>       sockets.  This is because...
>
>    2) win32 sockets, unlike unix fds, are not consecutively numbered
>       integers starting at 0.  Thus, it is _NOT_ a good idea to use an
>       array to map fds to events like select.c does; your array would
>       be enormous and sparse.
>
> A balanced tree implementation might an improvement here.  It would be
> nice if somebody would step up and write one.

select() under win32 only works on sockets, so it's only purpose is socket
selection.  Given that, select() is a poor choice - I/O completion ports
are much better; for one thing, they scale.  libiocp exists, although I
don't know at all what would be involved in the integration with libevent.

>> Looking around with google it seems that indeed, evdns et. al does not
>> build on windows (except when using e.g. cygwin, but thats trivial).
>>
>> So I wonder if libevent as a whole is supported under windows at all in
>> current versions?
>
> I'd like to have everything work on win32.  Trunk compiles on mingw
> fine.  I would like it also to compile under MSVC, but I don't have a
> copy of MSVC.  That's why diffs would be nice. :)

MS offer a free command line compiler and SDK.  Given they're free and
compatable with the commercial build environments, would they be a viable
choice of Win32 build environment?