On Monday 18 January 2010 22:47:05 Dale wrote: > In that case, ctrl alt F1 does nothing. You also need to understand > that most people don't even know how to use SysRq keys. I didn't and > had to do a hard shutdown. I had to actually pull the plug to do any > good. Luckily I knew how to get it to boot into single user mode so I > could disable hal otherwise I would be right back on the same screen > again with no mouse or keyboard. It would be really bad if even that > didn't work with devicekit. I'm not sure how it couldn't but we never > know do we?
Dale's experiences highlight a very important and very fundamental rule of desktop system design: As a developer you must completely and totally guarantee to the full limit of what is feasible, that the user will always have a usable keyboard, mouse and display after the desktop has launched. You can fallback to VGA resolution and the most basic keyboard layout possible if you need to, but you must give the user something and never leave them stranded. Anything else is just an epic fail. Magic SysRq falls so far short of this that it's not even worth contemplating. It's useful for mega-power users and kernel devs doing really way out things, but for normal users it might as well be invisible. Sure, it's documented in /usr/src/linux/Documentation/sysrq.txt. Well now, I offer two comments: I doubt that kernel docs are even installed on most user-centric distros, and anyone want to present an argument why the location of that file and it's contents might be construed as being "self-evident and/or obvious"? -- alan dot mckinnon at gmail dot com
