Calling an api sub

Posted on 2006-03-20
Medium Priority
Last Modified: 2012-08-13
I've asked this before and thought I was given enough info to resolve my problem , what am I doing wrong??.

Using LotusScript , which is essentially VB

Here is parts of the code

First my declaration:

Declare Sub Get_Noise Lib "C:\Bits\Raffles\SG100\SG100\ISAF_N1.dll" Alias "_Get_Noise_std@16" (Byte_PTR as String , Byval Bytes As Long,  Byval Error_Code As Long, Byval Exception As Long)

Dim gstr as string
Call Get_Noise(gstr,1,ErrorCode, Exception)

When the Call executes , the app crashes, so I'm sending wrong info to the dll. I've tried all sotrs of variations to no avail. Below is the only documentation I have for this dll. Addionally , what does the asterisk signify in the first line?
void Get_Noise( uchar *Byte_PTR, ulong Bytes, ulong *Error_Code, ulong
The call returns a string, of specified length, of random bytes, to
memory buffer at address Byte_PTR.

File Type: DLL

         Section contains the following Exports for ISAF_N1.DLL

                   0 characteristics
            3EADF853 time date stamp Tue Apr 29 03:58:11 2003
                 0.0 version
                   1 base
                  10 # functions
                  10 # names

            ordinal hint   name

                  1    0   DLL_Setup  (00001460)
                  3    1   Get_Noise  (000023b0)
                  4    2   Get_Noise_Ex  (000027f0)
                  7    3   Init_Noise_Thread  (000013a0)
                  8    4   Insert_Ciphertext  (00002b50)
                  9    5   Insert_Noise  (000019e0)
                  A    6   Release_UpdateLock  (00002d30)
                  C    7   SG100_Password  (00002f70)
                  E    8   SG100_Random  (00002e60)
                 10    9   Set_Status_Noise_Thread  (00001610)
                  2    A   _DLL_Setup_std@8  (00001440)
                  5    B   _Get_Noise_Ex_std@20  (000027c0)
                  6    C   _Get_Noise_std@16  (00002390)
                  B    D   _Release_UpdateLock_std@8  (00002d10)
                  D    E   _SG100_Password_std@16  (00002f50)
                  F    F   _SG100_Random_std@12  (00002e40)


        2000 .bss
        2000 .data
        1000 .edata
        1000 .idata
        1000 .rdata
        1000 .reloc
        1000 .rsrc
        1000 .sdata
        6000 .text

Question by:questfar
  • 2
LVL 17

Accepted Solution

zzzzzooc earned 1000 total points
ID: 16244091
>>what does the asterisk signify in the first line
They should define the parameters as pointers. The DLL is probably crashing your application because you passed the variables as ByVal instead of ByRef and it was modifying incorrect memory.

Something such as this may work:
Get_Noise(ByRef Byte_PTR As String, ByVal Bytes As Long, ByRef Error_Code As Long, ByRef Exception As Long)

I'm not sure about Byte_PTR, however. If you use String, you may have to assign a buffer (s = space(255)) or declare it was Byte Array, pass a dimensioned array to it and then possibly use StrConv() to get the ANSI/Unicode string. You may need to convert the string if you declare it as String also, as the DLL may return either of the two types.
LVL 46

Expert Comment

by:Sjef Bosman
ID: 16249203
I think you're not supposed to spend 1000 points on (in fact just) one question.

See http:Q_21782495.html
LVL 46

Expert Comment

by:Sjef Bosman
ID: 16249219
Ah drat!! Forget the link I posted!!

See http:Q_21782188.html

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