Re: How about a new pretest?

[Jason Rumney <jasonr@gnu.org>]

Richard Stallman wrote:
> I think we should try to fix these two problems now.  The first one
> should be easy.
>   
> ** make-network-process :nowait t doesn't work for non-local targets
>    on Windows.
>   
I have looked at this several times myself in the past, and others have 
looked since and made some more progress, but it isn't as simple as it 
should be.
The problem starts with the fact that the native select() on Windows 
only works for network sockets. But Emacs uses select() for subprocess 
I/O, so a long time ago, back when Emacs used an external program for 
network sockets, someone wrote a replacement for select() on w32 to 
handle subprocess I/O (and only subprocess I/O). Network socket support 
had to be added back in to this, then more recently :nowait support was 
added. The resulting code is difficult to understand and debug, and I'm 
sure if it was written from scratch to include non-blocking support for 
sockets, the code would look very different than it does today.

>    If it cannot be fixed, (featurep 'make-network-process '(:nowait t))
>    should return nil.
>   
I think this is probably the right solution for this release, unless 
someone who has the time and has not already tried to understand the 
code wants to try to fix it now.
Otherwise we could look at rewriting the select implementation from 
scratch after the release.