Date: Fri, 20 Sep 1996 19:41:14 +0930 (CST) From: Michael Smith <msmith@atrad.adelaide.edu.au> To: sos@freebsd.org Cc: pialkin@abel.pdmi.ras.ru, j_mini@efn.org, msmith@atrad.adelaide.edu.au, emulation@freebsd.org Subject: Re: New doscmd available for testing/munching Message-ID: <199609201011.TAA14497@genesis.atrad.adelaide.edu.au> In-Reply-To: <199609200851.KAA02961@ra.dkuug.dk> from "sos@freebsd.org" at Sep 20, 96 10:51:16 am
next in thread | previous in thread | raw e-mail | index | archive | help
sos@freebsd.org stands accused of saying: > > > > The problem is not with just screen mapping for drawing something(open > > screen memory for drawing is simple just mmap some part of /dev/mem & viola ...) > > My problem is that i am unabl to properly map some shadow screen for 0xA0000-0xB0000 address.... It's highly needable for programs working with screen background.. > > Hmm, I'm not sure we can do that, try ask John Dyson about that, he > is out "mastermind" in vm stuff... My 'conceptual model' for this went something like : - allocate 128K in the emulation process for screen memory. - when vt is activated, copy the area that falls under the physical screen memory to a temporary store. - mmap the screen memory onto your emulation's buffer. - copy your temporary store back. - when vt is deactivated, reverse the process. ... but I really don't know what happens when you mmap() screen memory onto a section of your process' space that is already mapped. Or would you swap between a mapping to screen memory and a file? Or could you map to _both_ screen memory and a file...? > Soren Schmidt (sos@FreeBSD.org) FreeBSD Core Team -- ]] Mike Smith, Software Engineer msmith@atrad.adelaide.edu.au [[ ]] Genesis Software genesis@atrad.adelaide.edu.au [[ ]] High-speed data acquisition and (GSM mobile) 0411-222-496 [[ ]] realtime instrument control (ph/fax) +61-8-267-3039 [[ ]] Collector of old Unix hardware. "Where are your PEZ?" The Tick [[
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199609201011.TAA14497>