Re: [ANNOUNCE]: LuaSocket 2.0.3 RC2

[Ignacio Burgueño <ignaciob@...>]

Jerome Vuarand wrote:
> 2009/11/3 Diego Nehab <diego@tecgraf.puc-rio.br>:
> > I agree getfd and setfd are not greatly thought out
> > features. That's why I call them hacks and that's why they
> > are not part of the documented API. They are there just for
> > debugging purposes and for people who want to use them at
> > their own risk.
> >
> > The problem is that these functions can lead to confusion on
> > Windows, since socket objects are not file descriptors
> > Having them in the API would seem to indicate it is ok to
> > obtain a file descriptor from a file handle and then insert
> > them in a socket object. This would not work on Windows and
> > I don't like the idea of having this on the API.
> >
> > Now, if what we are talking about functionality that allows
> > you to obtain this OS-dependent socket handle/descriptor and
> > create another LuaSocket object from it, we can discuss what
> > is the best API for it. It is a valid scenario that I had
> > not foreseen, and I'd be happy to add it to the library.
>
> I couldn't agree more. Leaking low level concepts in a high level API
> is likely to make it non-portable. Lua userdata bing opaque to Lua
> scripts is what makes it easy to nicely integrate any low level
> mechanism or paradigm into Lua, even though it makes their
> serialization impossible (but not all objects hidden behind a userdata
> are naturally serializable anyway).

Agreed, but maybe there's a way that we can combine Sam Roberts' 
suggestion, to have a socket relinquish its ownership and gaining access 
to an opaque identifier that is easily serializable (i.e. a number). 
Note that I'm not mentioning file descriptors. That identifier could be 
the fd but one must not rely on that. Only that I could get that 
identifier, send it to another lua_State and reconstruct a socket object 
from it and resume processing there.

Maybe something like
local raw = my_socket:detach()

==> send raw to another VM and there

local new_socket = socket.tcp(raw)
new_socket:read -- etc etc

Anyway, this, if it gets considered, will become part of LuaSocket 3 :)

Regards,
Ignacio