Re: anyone define port types?

[Chris Vine <chris@cvine.freeserve.co.uk>]

On Mon, 20 Jun 2016 09:34:26 +0200
Andy Wingo <wingo@pobox.com> wrote:
[snip]
> I must not be communicating clearly because this is definitely not
> what I am proposing.  The prompt doesn't service anything, and it's
> just the one user-space thread which is suspended, and when it
> suspends, it suspends back to the main loop which runs as usual,
> timers and all.
> 
>                         prompt
>    /------\ /------------\|/-----------\ /------------\ /----------\
>    | main --> run-thread -|>(user code)-->  read-char -->  waiter  |
>    | loop | |            |||           | |            | |          |
>    \------/ \------------/|\-----------/ \------------/ \--|-------/
>                           ^                                |
>                            \-------------------------------/
>    stack grows this way ->
> 
> The current-read-waiter aborts to a prompt.  That prompt is instated
> when the thread is run or resumed.  When you abort to that prompt, you
> add the FD to the poll set / main loop / *, remember the delimited
> continuation, and return to the main loop.  When the fd becomes
> readable or the gsource fires or whatever, you reinstate the
> delimited continuation via a new invocation of run-thread (prompt and
> all).

Ah right, that is clearer, thank you.  There would indeed be a prompt
for each user glib event source comprised in the "thread" abstraction,
which the read-waiter (or whatever) aborts to.  It is that abstraction
that I was missing and will need to look at.

Chris