From owner-freebsd-hackers Tue May 21 00:35:42 1996 Return-Path: owner-hackers Received: (from root@localhost) by freefall.freebsd.org (8.7.3/8.7.3) id AAA04765 for hackers-outgoing; Tue, 21 May 1996 00:35:42 -0700 (PDT) Received: from godzilla.zeta.org.au (godzilla.zeta.org.au [203.2.228.19]) by freefall.freebsd.org (8.7.3/8.7.3) with SMTP id AAA04760 for ; Tue, 21 May 1996 00:35:38 -0700 (PDT) Received: (from bde@localhost) by godzilla.zeta.org.au (8.6.12/8.6.9) id RAA27339; Tue, 21 May 1996 17:30:49 +1000 Date: Tue, 21 May 1996 17:30:49 +1000 From: Bruce Evans Message-Id: <199605210730.RAA27339@godzilla.zeta.org.au> To: freebsd-hackers@FreeBSD.org, j@uriah.heep.sax.de Subject: Re: Involking DDB Cc: dennis@etinc.com Sender: owner-hackers@FreeBSD.org X-Loop: FreeBSD.org Precedence: bulk >> Is there a way to start DDB without a system crash...ie run the kernel in >> some sort of monitoring mode on demand? >Several of them. >... >Hit the ``hot key'' on the PC keyboard. This is Ctrl-Alt-ESC by >default, though i think some syscons keymaps tweak it onto another >combination (which i forgot). I thought that Ctrl-PrintScreen was standard and Ctrl-Alt-ESC was the old-fashioned way :-). Both are BAD. The key releases for the shift keys should be handled by the driver in the debugger, and it isn't clear how they should be communicated to the standard driver except of course if the standard driver is abused for the debugger driver. It's safer to throw the key releases for non-shift keys away. >... `Debugger("foo");' in your code. `asm("int $3")' in your code. `breakpoint();' in your code. Your code may be a special lkm for monitoring for interesting events... Bruce