Weird Exceptio Access

[pedro c camargo]

This routine wprks perfect in most computers but is giving me a weird error on a few computer.

Exception Access violation (0x000005) 0x100039c3

If I put a msgbox "Test" line it works fine.

Is there a way to at least simulate the msgbox without actually showing anything?


Thanks

Pedro Camargo

----------------

IdeNumber = 1
HW32=0

proc = LoadLibrary("TVicHW32.DLL")
gethdid="Not Loaded"
IF proc THEN
                  
funcaddr = GetProcAddress(proc, "OpenTVicHW32")

IF funcaddr<> %NULL THEN
'msgbox "Text"
CALL DWORD funcaddr USING OpenTVicHW32X(HW32,"TVICHW32", "TVicDevice0") TO HW32
END IF
IF HW32<>0 THEN
funcaddr = GetProcAddress(proc, "GetActiveHW")
dummy=0
IF funcaddr<>0 THEN
CALL DWORD funcaddr USING GetActiveHWX(HW32) TO dummy
END IF
IF dummy<>0 THEN
    funcaddr = GetProcAddress(proc, "GetHDDInfo")
    CALL DWORD funcaddr USING GetHDDInfoX(HW32, IdeNumber, Master, HddInfo)
    'CALL GetHDDInfo(HW32, IdeNumber, Master, HddInfo)
    gethdid=UCASE$(TRIM$(HddInfo.Model)+"-"+TRIM$(HddInfo.SerialNumber))
    IF TRIM$(HddInfo.SerialNumber)="" THEN gethdid="No Info"
'    HW32 = CloseTVicHW32(HW32)
    funcaddr=GetProcAddress(proc, "CloseTVicHW32")
    IF funcaddr<>%NULL THEN
    CALL DWORD funcaddr USING CloseTVicHW32X(HW32) TO dummy
    END IF
END IF
END IF
CALL FreeLibrary(proc)
END IF

------------------
Pedro Camargo

[Lance Edmonds]

It sounds like the DLL could need some small amount of time to initialize itself before it's functions are called. Remember, the MSGBOX statement takes time to be displayed and responded to by the user.

Basically, I'd suggest that you should concentrate on tracking down the real cause of the problem, and forget trying to implement a MSGBOX.

Can you pinpoint the place in the code where the exception/GPF is raised? Can you step through it in the debugger to locate the problem, or for example, insert a line of code before each statement to write to a log file to indicate the position of execution.

I hope this helps!

------------------
Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>

[Scott Turchin]

In your WIndows or Winnt directory you will find a file named drwtsn32.log or something to that effect....

It will have all of the DLL's loaded at the time, will show the stack and will have something like this in it:

FAULT======>


Points to the fault.....may or may not help you but 0x000005 is generally either file permissions, or null pointer..
Check your asciiz or string's, BYVAL or lack of's in your functions.....

------------------
Scott

[This message has been edited by Scott Turchin (edited May 22, 2001).]

[Scott Turchin]

Check your case sensitivity on OpenTVicHW32X and then check the parameters as to whether you should be using byval, sending a pointer, etc.....

Try some asciiz statements
Param1 as asciiz * 120, then send it or send it as byval varptr(Param1)...


Also, not sure whether or not this is an activeX DLL (Ie VB6), but I have one called FREECCS.DLL that allows me to get that far, then blows up, and it turns out it's an AX DLl and I can't use it.....



------------------
Scott

[Lance Edmonds]

He says it works on some computers though, so the cause is probably more obscure...

------------------
Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>

[Sven Blumenstein]

>It sounds like the DLL could need some small amount of time to initialize itself before it's functions are called

Yes, sounds like this to me, too. Just try to insert

SLEEP 2000

------------------
E-Mail (home): mailto:[email protected][email protected]</A>
E-Mail (work): mailto:[email protected][email protected]</A>

[pedro c camargo]

Thanks for your suggestions.

I have already tried sleep 3000 and 5000. It does not work.

It works fine on most machines with NT/ Me, win95/98, it only has this problem on some Dell Servers with NT 4.0

And again, if I put a msgbox statement once I click on the box it works fine.


Does the msgbox triggers or resets something else?

Pedro Camargo

--- Error log ----
State Dump for Thread Id 0xcd

eax=01010984 ebx=01010600 ecx=00000000 edx=704f0000 esi=00000000 edi=00000000
eip=100039c3 esp=0012fc5c ebp=0012fd3c iopl=0 nv up ei ng nz ac pe cy
cs=001b ss=0023 ds=0023 es=0023 fs=0038 gs=0000 efl=00000293


function: <nosymbols>
1000399a ff1588700010 call dword ptr [10007088] ds:10007088=77f02b02
100039a0 8d8384030000 lea eax,[ebx+0x384] ds:01010984=00000000
100039a6 894304 mov [ebx+0x4],eax ds:01f0f006=????????
100039a9 33f6 xor esi,esi
100039ab 89b540ffffff mov [ebp+0xffffff40],esi ss:0012fc7c=00000000
100039b1 6683fe03 cmp si,0x3
100039b5 7d46 jge 100039fd
100039b7 897dfc mov [ebp-0x4],edi ss:0102e742=????????
100039ba 0fbfce movsx ecx,si
100039bd 8b953cffffff mov edx,[ebp+0xffffff3c] ss:0012fc78=704f0000
FAULT ->100039c3 668b044a mov ax,[edx+ecx*2] ds:00000000=????
100039c7 663bc7 cmp ax,di
100039ca 7416 jz 100039e2
100039cc 33c9 xor ecx,ecx
100039ce 8a8b95030000 mov cl,[ebx+0x395] ds:01010995=00
100039d4 6689844b84030000 mov [ebx+ecx*2+0x384],ax ds:00000384=????
100039dc fe8395030000 inc byte ptr [ebx+0x395] ds:01010995=00
100039e2 c745fcffffffff ss:0102e742=????????
mov dword ptr [ebp-0x4],0xffffffff
100039e9 e80e000000 call 100039fc
100039ee 46 inc esi
100039ef ebba jmp 100039ab
100039f1 8b5d08 mov ebx,[ebp+0x8] ss:0102e742=????????

*----> Stack Back Trace <----*

FramePtr ReturnAd Param#1 Param#2 Param#3 Param#4 Function Name
0012fd3c 0040f6fc 01010600 00134ce4 001349e4 00416746 <nosymbols>

*----> Raw Stack Dump <----*
0012fc5c 01 00 00 00 00 00 00 00 - 48 fd 12 00 ad be f6 77 ........H......w
0012fc6c 00 00 00 00 2c 06 01 01 - 4c fd 12 00 00 00 4f 70 ....,...L.....Op
0012fc7c 00 00 00 00 69 63 48 57 - 33 32 00 ff b0 fc 12 00 ....icHW32......
0012fc8c dc 4d f6 77 94 00 00 00 - 04 00 00 00 00 00 00 00 .M.w............
0012fc9c 65 05 00 00 02 00 00 00 - 53 65 72 76 69 63 65 20 e.......Service
0012fcac 50 61 63 6b 20 36 00 00 - fd 3a f1 77 00 00 13 00 Pack 6...:.w....
0012fcbc 00 00 00 00 c8 4a 13 00 - a3 07 00 00 f8 eb fd 7f .....J..........
0012fccc 00 7b 00 10 90 4c 13 00 - 00 37 00 10 00 00 00 00 .{...L...7......
0012fcdc 18 00 00 00 01 00 00 00 - f0 47 13 00 ab d8 f1 77 .........G.....w
0012fcec 29 12 b2 77 00 00 13 00 - 00 00 00 00 10 00 00 00 )..w............
0012fcfc ff 14 34 65 28 b2 bc 77 - 10 00 00 00 10 00 00 00 ..4e(..w........
0012fd0c bf 3d 34 65 10 00 00 00 - 01 00 00 00 0c 7d 41 00 .=4e.........}A.
0012fd1c 50 fe 12 00 4c fd 12 00 - 96 38 41 00 a4 fa 12 00 P...L....8A.....
0012fd2c e0 ff 12 00 5c 3f 00 10 - b0 71 00 10 00 00 00 00 ....\?...q......
0012fd3c 50 fe 12 00 fc f6 40 00 - 00 06 01 01 e4 4c 13 00 [email protected]..
0012fd4c e4 49 13 00 46 67 41 00 - 00 00 00 00 00 37 00 10 .I..FgA......7..
0012fd5c 00 00 00 10 00 00 00 00 - 01 00 00 00 00 00 00 00 ................
0012fd6c 00 00 00 00 00 00 00 00 - 00 00 00 00 00 00 00 00 ................
0012fd7c 00 00 00 00 00 00 00 00 - 00 00 00 00 00 00 00 00 ................
0012fd8c 00 00 00 00 00 00 00 00 - 00 00 00 00 00 00 00 00 ................

State Dump for Thread Id 0xc9

eax=100015a0 ebx=00134da0 ecx=0012fc50 edx=00000000 esi=7ffdf000 edi=00000000
eip=77f682cb esp=0120ff24 ebp=0120ff78 iopl=0 nv up ei pl nz ac pe cy
cs=001b ss=0023 ds=0023 es=0023 fs=0038 gs=0000 efl=00000213


function: NtWaitForMultipleObjects
77f682c0 b8c4000000 mov eax,0xc4
77f682c5 8d542404 lea edx,[esp+0x4] ss:0210e92b=????????
77f682c9 cd2e int 2e
77f682cb c21400 ret 0x14
77f682ce 8bc0 mov eax,eax

*----> Stack Back Trace <----*

FramePtr ReturnAd Param#1 Param#2 Param#3 Param#4 Function Name
0120ff78 77f1cd76 00000010 01010748 00000000 ffffffff ntdll!NtWaitForMultipleObjects




------------------
Pedro Camargo

[Sven Blumenstein]

> 0012fc9c 65 05 00 00 02 00 00 00 - 53 65 72 76 69 63 65 20 e.......Service
> 0012fcac 50 61 63 6b 20 36 00 00 - fd 3a f1 77 00 00 13 00 Pack 6...:.w....

Perhaps a Problem with the NT Service Pack


------------------
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E-Mail (work): mailto:[email protected][email protected]</A>

[pedro c camargo]

I have this problem on 3 different machines Dell with SP 6.

I have also tried it on other machines with sp 6 and it works fine.


Pedro Camargo

------------------
Pedro Camargo

[Florent Heyworth]

Running SP6 or SP6a?


Florent

------------------

[pedro c camargo]

Some have 6 others have 6a.

It even works on machines with sp 4

Thanks

Pedro

------------------
Pedro Camargo

[Daniel Corbier]

pedro, do you by any chance have a sub or function anywhere in
the dll or in the program calling it, which takes an asciiz
argument? if so, check to see that you are not passing an
empty string to that routine. if so, that will likely cause a
problem which may manifest itself in an entirely different
location of your program, next to some innocent-looking code.
it may also not manifest itself at all. something like this
happened to me, and it was very tricky to track it down.

to check for this, make sure you use (at least temporarily):

$debug error on

then in every function/sub which takes an asciiz argument, add
an on error goto statement which prints the error. in
my case the actual error was trigged in a line similar to:

temp$ = ucase$(arg)

where arg is an argument passed as asciiz. however, the crash
happed from a host visual basic program. on further inspection,
it appeared to be caused by a an innocent line of pb code
somewhere totally removed from the actual source of the error.

unfortunately, i still haven't found a solid way to check for
null in this context. in a separate thread at http://www.powerbasic.com/support/pb...ad.php?t=18246
lance suggested that i check the varptr of the asciiz string
before using it. it looked like a great solution, but it didn't
work when i tried it.


------------------
daniel corbier
ucalc fast math parser
http://www.ucalc.com

[Florent Heyworth]

Or: can you post the original C function prototypes as well
as your translation of them?

Cheers

Florent

------------------

[Scott Turchin]

Hmmm is it a Microsoft install of Windows or the original OEM versio nof Windows that DELL was allowed to modify?


Also, try re-registering the DLL, may or may not have anything to do with it but cannot hurt...
REGSVR32.exe DLLNAME.DLL



------------------
Scott

[pedro c camargo]

The library is supposed to load dinamically.

I think is a dll problem.

My question is why if I insert a msgbox statement before the opne function it works fine?

I have already tried replacing the msgbox with sleep , a do..loop, nothing works.

I am trying to simulate a msgbox using a modal dialog.

I will be ready in a few minutes and I will let you know if that works.


Thanks for your assistance,

Pedro

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Pedro Camargo

[pedro c camargo]

Ok. I got somethin new.

I replaced the msgbox with a modal dialog and it also works when I click the close button in the dialog.

Then I put a 2 sec. timer to automatically close the modal dialog and it does not work.

???????????

Pedro

------------------
Pedro Camargo