Date: Tue, 17 MAR 1998 18:54:08 +0000 (GMT) From: Dave Walker Subject: Acorn Developer News 17/03/98: Ursula Kernel Spec, etc To: isvquery@acorn.com Hi folks... Acorn Developer News 17/03/98 Another short missive: Ursula Kernel Spec ------------------ This is now available as http://www.art.acorn.co.uk/SALES/DEVELOPERS/resource/docs/api/ursula/kernel.eps (for those of you with PostScript printers) and http://www.art.acorn.co.uk/SALES/DEVELOPERS/resource/docs/api/ursula/kernel.html (for those of you without). You may notice a few things about this doc; in addition to giving you memory map details, info about the new screen caching system, the stretched command line and extended handling of dynamic areas, it includes the spec for an extension to the relocatable module format in order to increase service call distribution efficiency. Before you all throw your hands up in the air in horror at expecting to have to rebuild all the modules in all your code, you should bear the following in mind: * Modules which don't make use of a service handler call are not affected * There aren't any backward compatibility problems with the new format (ie new-format modules can safely be shipped to run on pre-Ursula kit...) * Existing modules which use a service call handler should still run (unless other issues are involved), but the cost of service call distribution goes up significantly and thus slows the machine down * It should be possible to produce a patcher to convert existing module binaries to the new format; we're looking at this * Of course, we'd like you all to patch your modules at the source, especially when you next revisit them... Other Specs ----------- I've been promised more specs this week; I'm working my way through the mountain of CDFS stuff at the moment, but figured it would be worthwhile to get the kernel docs out ASAP. FileCore should be next on my list... Cheers, -- Dave Walker, Engineering Support Manager Acorn Computers Ltd Tel: +44 (0) 1223 725233 Acorn House, 645 Newmarket Road Fax: +44 (0) 1223 725333 Cambridge, CB5 8PB, United Kingdom WWW: http://www.acorn.co.uk/