I’m now coming to the end of the series of episodes about the C-API of VASmalltalk. Much more could be presented, much more in detail – but that’s not the idea of these episodes. I hope, that you get the idea or an overview what features you have, when trying to connect VASmalltalk to another (mainly C) programming language.
In this last episode we have another look on primitives and how they can be used to build interrupt handlers, which are mainly a nice way to communicate from an independent C-threads to the main Smalltalk-thread.
InterruptHandlers may be used in complexed c-based subsystems to inform Smalltalk about progress informations. As an example one could use the c library “curl” to retrieve data from various sources (ftp, html, …) handled by native os-threads and all that stuff is done independently from Smalltalk and Smalltalk only gets progress informations from those tasks and perhaps success/failure information from that subsystem about these tasks.