From: CSBVAX::MRGATE!@KL.SRI.Com:munnari!ditmela.oz!SMART%ditmelb.OZ@seismo.CSS.GOV@SMTP 30-JUN-1987 09:15 To: EVERHART Subj: Disassembly, NOTRACEBACK, dynamically loaded shareable images Received: from seismo.CSS.GOV by KL.SRI.COM with TCP; Mon 29 Jun 87 21:38:14-PDT Received: from munnari.UUCP by seismo.CSS.GOV (5.54/1.14) with UUCP id AA02504; Tue, 30 Jun 87 00:37:41 EDT Message-Id: <8706300437.AA02504@seismo.CSS.GOV> Received: from ditmela (via mulga) by munnari.oz with SunIII (5.5) id AA03532; Tue, 30 Jun 87 13:27:53 EST Received: from ditmelb.oz.au by ditmela.oz (3.2/SMI-3.0DEV3) id AA18200; Tue, 30 Jun 87 10:05:39 EST Date: Tue, 30 Jun 87 10:05 +1000 From: Robert Smart Subject: Disassembly, NOTRACEBACK, dynamically loaded shareable images To: info-vax@KL.SRI.COM X-Vms-To: IN%"info-vax@sri-kl.arpa" It is quite easy to change an image linked /NOTRACEBACK to be debuggable: PATCH/ABSOLUTE x.EXE and set the low order bit of location 20 (this seems to mean changing 01000028 to 01000029). Now set the longword at 34 (which is 0) to the contents of the longword at 30. Now set the longword at 30 to be the correct start address for the debugger: currently 7FFEDF68. Update and exit and you've done it. I hoped to use this trick to debug a dynamically loaded shareable image (a protocol handler for MAIL). Does anybody know how to tell the debugger that a shareable image has suddenly arrived at a particular address? I would prefer it if the debugger would notice arriving shareable images itself, but perhaps that is asking too much. Robert Smart, CSIRO Division of Information Technology, Australia