[Freeciv-Dev] Re: Working on client APIs

[Jed Davis <jldavis@xxxxxxxxxxxxxx>]

--On Saturday, 8 July 2000 2:24 PM +0200 Raimar Falke 
<hawk@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
> I have started on defining and implementing an API for client side AI. The
> basic structure in my current design is a general layer, which does
> caching and the network stuff. This layer exports an API to the upper
> layer, which  I termed "control program". This part can be written in any
> language. The interaction is quite simple throught callbacks: the lower
> layer sniffs a packet from the network, updates the cache and calls a
> notify callback in the upper layer. The upper layer then can use the
> cached data to make a decision and call some set_* method in the lower
> layer. My test control  program is now written in C and can at least call
> turn_done() if it gets  a new_year_notify. This allows to get a whole
> game from -4000 till the server-AI kills me in some minutes.
This would also be very useful for client-side 
scripting/automation/whatever.  However I'm not quite clear what a callback 
would involve here: I first thought that it would involve calling a C 
function (which could dispatch the call to an embedded interpreter), but 
the "written in any language" implies that these callbacks involve some 
kind of IPC with the controller running as a separate process, which is 
probably a better idea in the long run.  Since I'm sort of working on 
(read: planning and trying in vain to find time for) GUILE scripting, I'd 
appreciate any information on this.
> There is no multithreading in this design. I'm not sure if there is a
> situation where mutlithreading is needed. Since I don't know any thread
> package for C can somebody recommend one?
I know of pthread (POSIX threads), which as far as I know is fairly 
widespread.
--Jed