Re: Options to replace select in Nsock

[David Fifield <david () bamsoftware com>]

On Sat, Jun 20, 2009 at 07:20:04PM -0400, Michael Pattrick wrote:
> I agree with Doug, a statefull API should be used. He gives some
> excellent reasons, as an additional reason, only the latest version of
> windows supports Poll while CreateIoCompletionPort has been supported
> since windows 2000, so going this route will acutely be more
> compatible.

The problem with the advanced APIs is that they are platform-specific.
So unless we are going to support (and debug, and maintain) all of them,
there still has to be a select/poll fallback. The stateful APIs should
be considered an addition to a select/poll compatibility implementation,
not a replacement for it.

And because select can't handle many descriptors and poll isn't
available everywhere select is, I think we'll need to base the
compatibility implementation on poll, with a fallback to a select-based
implementation of poll for systems without poll. Brandon found an
example of this poll-select fallback.

> In the meantime, couldn't Nsock be quickly adapted to use multiple
> calls to select with different FD_SET arrays when tracking >
> FD_SETSIZE items?

I don't think you can use select that way. Each fd_set is indexed
starting at zero.

David Fifield

_______________________________________________
Sent through the nmap-dev mailing list
http://cgi.insecure.org/mailman/listinfo/nmap-dev
Archived at http://SecLists.Org