info-vax@ucbvax.ARPA (03/18/85)
From: GKN%OAK.SAINET.MFENET@LLL-MFE.ARPA
Getting rid of the traceback handler in an image isn't too hard if you're
willing to use HexZap (or Patch/Absolute under V4). Take the image file
in question and do an $ Analyze/Image/Interactive on it. Get to the section
where it lists the transfer addresses (there are 3) and copy them down
somewhere. Now dump the first block of the image and spot those transfer
addresses. The traceback handler will be called before the actual entry
point for the image to set up the initial stack frame with the condition
handler which produces that nasty stack trace.
These transfer addresses are usually at 30H in the first block, but are
not fixed. At any rate, simply move down the real program start address
on top of the traceback handler with HexZap and zero out the call to the
traceback handler. I seem to recall that one of the VMS System Dispatches
had a command procedure to automate this, but I'm at home and they're at
the office. So, here's a complete example:
[Log file DSK2:[GKN]FOO.LOG;1 created by TTLINK V01.10 on 16-MAR-1985 11:16:35.59]
$ type foo.mar
.title foo
.psect code exe,rd,nowrt,pic,shr,page
.entry start,0
ret
.end start
$ macro foo
$ link foo
$ analyze/image/interactive foo
IMAGE HEADER
Fixed Header Information
image format major id: 02, minor id: 04
header block count: 1
image type: executable (IHD$K_EXE)
I/O channel count: default
I/O page count: default
linker flags:
(0) IHD$V_LNKDEBUG 0
(1) IHD$V_LNKNOTFR 0
(2) IHD$V_NOP0BUFS 0
(3) IHD$V_PICIMG 1
(4) IHD$V_P0IMAGE 0
Press RETURN to continue, or enter a period (.) for next file:
Image Activation Information
first transfer address: %X'7FFEDF68'
second transfer address: %X'00000200'
third transfer address: %X'00000000'
Press RETURN to continue, or enter a period (.) for next file:
.
The analysis uncovered NO errors.
ANALYZE/IMAGE/INTERACTIVE FOO
$ dump/block=(start:1,end:1) foo.exe
Dump of file DSK2:[GKN]FOO.EXE;1 on 16-MAR-1985 11:13:22.89
File ID (2347,18,0) End of file block 4 / Allocated 4
Virtual block number 1 (00000001), 512 (0200) bytes
00000000 FFFFFFFF FFFFFFFF 00000101 34303230 00000000 004C0040 00300084 ..0.@.L.....0204................ 000000
00000000 00000000 00000200 7FFEDF68 00000400 00000000 A155A224 01000008 ....$.U.........h............... 000020
00003001 00000000 00000000 00000000 4F4F4603 00000001 00000000 00000004 .............FOO.............0.. 000040
00000000 00003630 2D333005 008DA155 A2249100 00000000 00000000 00000000 ..............$.U....03-06...... 000060
0000040A 00000002 00010010 00000002 00000080 00000001 00010010 00000000 ................................ 000080
FFFFFFFF FFFFFFFF FFFFFFFF FFFF0000 FD00008C 003FFFEC 0014000C 00000003 ..........?..................... 0000A0
FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF ................................ 0000C0
FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF ................................ 0000E0
FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF ................................ 000100
FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF ................................ 000120
FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF ................................ 000140
FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF ................................ 000160
FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF ................................ 000180
FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF ................................ 0001A0
FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF ................................ 0001C0
FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF ................................ 0001E0
$ r hexzap
ZAP>foo.exe
_0:30/
00:0030/ DF68
_200
_
00:0032/ 7FFE
_0
_
00:0034/ 0200
_0
_
00:0036/ 0000
_x
gkn
------------------------------------------
Arpa: GKN%OAK.SAInet@LLL-MFE
USPS: Gerard K. Newman
Science Applications International
800 Oak Ridge Turnpike
Oak Ridge, TN 37830
AT&T: (615) 482-9031