[Migrated content. Thread originally posted on 31 January 2011]
Hi all,
I'm using Visual Code (2008) edition and i need to find out how to convert the following VB code into COBOL code.
I have a DLL on my system called “Winscard.dll” but I can’t get my project to access it.
The code I’m trying to convert is :-
Public Declare Function SCardEstablishContext Lib "Winscard.dll" (ByVal dwScope As Integer, _
ByVal pvReserved1 As Integer, _
ByVal pvReserved2 As Integer, _
ByRef phContext As Integer) As Integer
And I’ve tried adding the DLL as a project ref but cant seem to access it.
Any ideas/help much appreciated as I'm a bit stuck at the moment.
Many thanks
Neil.
If this is a native project you should be able to link with library called Winscard.lib.
The API SCardEstablishContext is WinAPI, so you would need to call SCardEstablishContext with call-convention 74, also because it is not all upper characters in the API, use the compiler directive CASE too.
If it is managed application you can CALL it in the same way but instead of linking with Winscard.lib use ILPINVOKE"winscard.dll" (or add a reference to the winscard.dll) and ensure you target the right bit'ness too... ie: through the IDE target x86 or use ILTARGET"x86" or ILTARGET"x64".
[Migrated content. Thread originally posted on 31 January 2011]
Hi all,
I'm using Visual Code (2008) edition and i need to find out how to convert the following VB code into COBOL code.
I have a DLL on my system called “Winscard.dll” but I can’t get my project to access it.
The code I’m trying to convert is :-
Public Declare Function SCardEstablishContext Lib "Winscard.dll" (ByVal dwScope As Integer, _
ByVal pvReserved1 As Integer, _
ByVal pvReserved2 As Integer, _
ByRef phContext As Integer) As Integer
And I’ve tried adding the DLL as a project ref but cant seem to access it.
Any ideas/help much appreciated as I'm a bit stuck at the moment.
Many thanks
Neil.
Are you converting to managed code or unmanaged code COBOL?
Net Express or Visual COBOL?
If you are converting to an unmanaged code COBOL program you can do this as follows:
$SET CASE
01 dwScope pic x(4) comp-5.
01 pvReserved1 pic x(4) comp-5.
01 pvReserved2 pic x(4) comp-5.
01 phContext pic x(4) comp-5.
01 retValue pic x(4) comp-5.
01 procPtr procedure-pointer.
procedure division.
set procPtr to entry "Winscard.dll"
call "SCardEstablishContext"
using by value dwScope
pvReserved1
pvReserved2
by reference phContext
returning retValue
end-call
[Migrated content. Thread originally posted on 31 January 2011]
Hi all,
I'm using Visual Code (2008) edition and i need to find out how to convert the following VB code into COBOL code.
I have a DLL on my system called “Winscard.dll” but I can’t get my project to access it.
The code I’m trying to convert is :-
Public Declare Function SCardEstablishContext Lib "Winscard.dll" (ByVal dwScope As Integer, _
ByVal pvReserved1 As Integer, _
ByVal pvReserved2 As Integer, _
ByRef phContext As Integer) As Integer
And I’ve tried adding the DLL as a project ref but cant seem to access it.
Any ideas/help much appreciated as I'm a bit stuck at the moment.
Many thanks
Neil.
hi, to be honest i dont mind which way the code is done as long as it works.
i am using visual studio 2008 with nx5.1 so if it can be done any .NET way that i'm assuming that would be a better way to handle the code.
can you pls also advise how to convert to COBOL the "ALIAS" command, see lines of VB code below:-
Public Declare Function SCardListReaders Lib "Winscard.dll" Alias "SCardListReadersA"
(ByVal hContext As Integer, _
ByVal mzGroup As String, _
ByVal ReaderList As String, _
ByRef pcchReaders As Integer) As Integer
i have tried the following:-
set procPtr to entry "Winscard.dll"
call "SCardListReadersA"
using by value hContext
mzGroup
ReaderList
by reference pcchReaders
returning retValue
end-call
but it doesnt work and the IDE shows a warning on the retValue of
Warning 1 Number of parameters in CALL (4) different from number in target method (0)
many thanks for your help.
[Migrated content. Thread originally posted on 31 January 2011]
Hi all,
I'm using Visual Code (2008) edition and i need to find out how to convert the following VB code into COBOL code.
I have a DLL on my system called “Winscard.dll” but I can’t get my project to access it.
The code I’m trying to convert is :-
Public Declare Function SCardEstablishContext Lib "Winscard.dll" (ByVal dwScope As Integer, _
ByVal pvReserved1 As Integer, _
ByVal pvReserved2 As Integer, _
ByRef phContext As Integer) As Integer
And I’ve tried adding the DLL as a project ref but cant seem to access it.
Any ideas/help much appreciated as I'm a bit stuck at the moment.
Many thanks
Neil.
actually its almost working except returning the card reader name, so thought i would post the full vb code that need converting in case i'm missing something.
Private Sub frmMain_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
For ctr = 0 To 255
sReaderList = sReaderList vbNullChar
Next
ReaderCount = 255
' 1. Establish context and obtain G_hContext handle
G_retCode = ModWinsCard.SCardEstablishContext(ModWinsCard.SCARD_SCOPE_USER, 0, 0, G_hContext)
If G_retCode <> ModWinsCard.SCARD_S_SUCCESS Then
WriteLog(GetScardErrMsg(G_retCode))
Exit Sub
End If
' 2. List PC/SC card readers installed in the system
G_retCode = ModWinsCard.SCardListReaders(G_hContext, "", sReaderList, ReaderCount)
If G_retCode <> ModWinsCard.SCARD_S_SUCCESS Then
WriteLog(GetScardErrMsg(G_retCode))
Exit Sub
End If
Call LoadListToControl(cbReaderList, sReaderList)
cbReaderList.SelectedIndex = 0
ioRequest.dwProtocol = Protocol
ioRequest.cbPciLength = Len(ioRequest)
WriteLog("Program Ready")
WriteLog("Select reader, insert mcu card and connect.")
End Sub
Public Declare Function SCardEstablishContext Lib "Winscard.dll" (ByVal dwScope As Integer, _
ByVal pvReserved1 As Integer, _
ByVal pvReserved2 As Integer, _
ByRef phContext As Integer) As Integer
Public Declare Function SCardListReaders Lib "Winscard.dll" Alias "SCardListReadersA" (ByVal hContext As Integer, _
ByVal mzGroup As String, _
ByVal ReaderList As String, _
ByRef pcchReaders As Integer) As Integer
Im getting values in pcchReaders of 54 which is the length of the string that should be in ReaderList but its null.
Really appreciate your help in sorting this out.
[Migrated content. Thread originally posted on 31 January 2011]
Hi all,
I'm using Visual Code (2008) edition and i need to find out how to convert the following VB code into COBOL code.
I have a DLL on my system called “Winscard.dll” but I can’t get my project to access it.
The code I’m trying to convert is :-
Public Declare Function SCardEstablishContext Lib "Winscard.dll" (ByVal dwScope As Integer, _
ByVal pvReserved1 As Integer, _
ByVal pvReserved2 As Integer, _
ByRef phContext As Integer) As Integer
And I’ve tried adding the DLL as a project ref but cant seem to access it.
Any ideas/help much appreciated as I'm a bit stuck at the moment.
Many thanks
Neil.
The strings should be passed by reference in COBOL and should be NULL terminated.
Try:
call "SCardListReaderA"
using by value hContext
by reference mzGroup
ReaderList
pcchReaders
returning retValue
end-call
[Migrated content. Thread originally posted on 31 January 2011]
Hi all,
I'm using Visual Code (2008) edition and i need to find out how to convert the following VB code into COBOL code.
I have a DLL on my system called “Winscard.dll” but I can’t get my project to access it.
The code I’m trying to convert is :-
Public Declare Function SCardEstablishContext Lib "Winscard.dll" (ByVal dwScope As Integer, _
ByVal pvReserved1 As Integer, _
ByVal pvReserved2 As Integer, _
ByRef phContext As Integer) As Integer
And I’ve tried adding the DLL as a project ref but cant seem to access it.
Any ideas/help much appreciated as I'm a bit stuck at the moment.
Many thanks
Neil.
Sorry but that does work.
I have got the following code to work except for returning the Card Readers name in ReaderList it just shows null. However if I use the VB code then it returns the Card Readers name which is a string that is 54 chars long. Which my Cobol program does return in the pcchReaders field i.e. if i hover over this field in the IDE debug it starts as 255 but once performed the function it has a value of 54 in it.
Can some one pls advise what I am doing wrong as Im struggling to convert the VB code into COBOL.
My current code as it stands is:-
method-id. "ListReaders" public static.
local-storage section.
01 mzGroup string value "".
01 ReaderList string value null.
01 pcchReaders binary-long.
01 phContext binary-long.
01 retValue binary-long.
01 procPtr procedure-pointer.
procedure division returning lnk-key as string.
* Public Declare Function SCardListReaders Lib "Winscard.dll" Alias "SCardListReadersA"
* (ByVal hContext As Integer, _
* ByVal mzGroup As String, _
* ByVal ReaderList As String, _
* ByRef pcchReaders As Integer) As Integer
set phContext to -855572480
set pcchReaders to 255
set procPtr to entry "Winscard.dll"
call "SCardListReadersA"
using by value phContext
by value mzGroup
by value ReaderList
by reference pcchReaders
returning retValue
end-call
set lnk-key to retValue
set lnk-key to retValue.
goback.
end method "ListReaders".
[Migrated content. Thread originally posted on 31 January 2011]
Hi all,
I'm using Visual Code (2008) edition and i need to find out how to convert the following VB code into COBOL code.
I have a DLL on my system called “Winscard.dll” but I can’t get my project to access it.
The code I’m trying to convert is :-
Public Declare Function SCardEstablishContext Lib "Winscard.dll" (ByVal dwScope As Integer, _
ByVal pvReserved1 As Integer, _
ByVal pvReserved2 As Integer, _
ByRef phContext As Integer) As Integer
And I’ve tried adding the DLL as a project ref but cant seem to access it.
Any ideas/help much appreciated as I'm a bit stuck at the moment.
Many thanks
Neil.
Just found out if I take the following lines out of the VB code it also returns blank.
For ctr = 0 To 255
sReaderList = sReaderList vbNullChar
Next
ReaderCount = 255
Could some one pls advise what the COBOL code is for this?
Many thanks
[Migrated content. Thread originally posted on 31 January 2011]
Hi all,
I'm using Visual Code (2008) edition and i need to find out how to convert the following VB code into COBOL code.
I have a DLL on my system called “Winscard.dll” but I can’t get my project to access it.
The code I’m trying to convert is :-
Public Declare Function SCardEstablishContext Lib "Winscard.dll" (ByVal dwScope As Integer, _
ByVal pvReserved1 As Integer, _
ByVal pvReserved2 As Integer, _
ByRef phContext As Integer) As Integer
And I’ve tried adding the DLL as a project ref but cant seem to access it.
Any ideas/help much appreciated as I'm a bit stuck at the moment.
Many thanks
Neil.
In your VB code:
For ctr = 0 To 255
sReaderList = sReaderList vbNullChar
Next
ReaderCount = 255
What is sReaderList declared as? What is the purpose of that loop?
[Migrated content. Thread originally posted on 31 January 2011]
Hi all,
I'm using Visual Code (2008) edition and i need to find out how to convert the following VB code into COBOL code.
I have a DLL on my system called “Winscard.dll” but I can’t get my project to access it.
The code I’m trying to convert is :-
Public Declare Function SCardEstablishContext Lib "Winscard.dll" (ByVal dwScope As Integer, _
ByVal pvReserved1 As Integer, _
ByVal pvReserved2 As Integer, _
ByRef phContext As Integer) As Integer
And I’ve tried adding the DLL as a project ref but cant seem to access it.
Any ideas/help much appreciated as I'm a bit stuck at the moment.
Many thanks
Neil.
from VB code:-
Dim sReaderList As String
but i dont know why it does it but i do know if i take out
For ctr = 0 To 255
sReaderList = sReaderList vbNullChar
Next
or
ReaderCount = 255
then i dont get any values if sReaderList how ever if i run the code as above i get :-
"SCM Microsystems Inc. SCR33x USB Smart Card Reader 0"
but although the COBOL code will return a value in ReaderCount im still getting nothing in sReaderList
[Migrated content. Thread originally posted on 31 January 2011]
Hi all,
I'm using Visual Code (2008) edition and i need to find out how to convert the following VB code into COBOL code.
I have a DLL on my system called “Winscard.dll” but I can’t get my project to access it.
The code I’m trying to convert is :-
Public Declare Function SCardEstablishContext Lib "Winscard.dll" (ByVal dwScope As Integer, _
ByVal pvReserved1 As Integer, _
ByVal pvReserved2 As Integer, _
ByRef phContext As Integer) As Integer
And I’ve tried adding the DLL as a project ref but cant seem to access it.
Any ideas/help much appreciated as I'm a bit stuck at the moment.
Many thanks
Neil.
The following code works for me and returns a good result:
$set ILPINVOKE"winscard.dll"
id division.
program-id. testreaders.
special-names.
call-convention 66 is winapi.
working-storage section.
78 SCARD-SCOPE-USER value 0.
01 phContext binary-long.
01 mzGroup pic x(256) value spaces.
01 ReaderList pic x(256) value all low-values.
01 pcchReaders binary-long.
01 retValue binary-long.
procedure division.
call winapi "SCardEstablishContext"
using by value SCARD-SCOPE-USER
by value 0
by value 0
by reference phContext
returning RetValue
end-call
move length of ReaderList to pcchReaders
call winapi "SCardListReadersA"
using by value phContext
by value 0
by reference ReaderList
by reference pcchReaders
returning retValue
end-call
stop run.
[Migrated content. Thread originally posted on 31 January 2011]
Hi all,
I'm using Visual Code (2008) edition and i need to find out how to convert the following VB code into COBOL code.
I have a DLL on my system called “Winscard.dll” but I can’t get my project to access it.
The code I’m trying to convert is :-
Public Declare Function SCardEstablishContext Lib "Winscard.dll" (ByVal dwScope As Integer, _
ByVal pvReserved1 As Integer, _
ByVal pvReserved2 As Integer, _
ByRef phContext As Integer) As Integer
And I’ve tried adding the DLL as a project ref but cant seem to access it.
Any ideas/help much appreciated as I'm a bit stuck at the moment.
Many thanks
Neil.
Yep that works many thanks for all your help in this matter.
Out of interest is there any way of coding this using the .NET way?
[Migrated content. Thread originally posted on 31 January 2011]
Hi all,
I'm using Visual Code (2008) edition and i need to find out how to convert the following VB code into COBOL code.
I have a DLL on my system called “Winscard.dll” but I can’t get my project to access it.
The code I’m trying to convert is :-
Public Declare Function SCardEstablishContext Lib "Winscard.dll" (ByVal dwScope As Integer, _
ByVal pvReserved1 As Integer, _
ByVal pvReserved2 As Integer, _
ByRef phContext As Integer) As Integer
And I’ve tried adding the DLL as a project ref but cant seem to access it.
Any ideas/help much appreciated as I'm a bit stuck at the moment.
Many thanks
Neil.
I am not sure what you are referring to when you say "the .NET way"?
Are you referring to the way it was done in VB?
This is just an example, you could have just as easily placed this code inside of a method as in a procedural program as shown in the example.
I used COBOL PIC X items instead of .NET strings because you are actually doing a Platform Invoke (P/Invoke) under the covers here to call an unmanaged Windows API function from within a managed code assembly.
This means that the strings are passed as pointers to a memory address and not as .NET string objects.
The P/Invoke complexity is handled by the compiler and is hidden from the user so you need not be concerned with items like pinned pointers, etc.
As far as "the .NET way" goes, COBOL provides support for data items defined as either COBOL types or .NET types and automatically converts between the two when possible.
This gives you the best of both worlds!
