Problem with DHCPEnumSubnetClients

Hi!
I'm using VB6 and I've a problem with DHCPEnumSubnetClinents API.

Declare Function DhcpEnumSubnetClients Lib "Dhcpsapi" (ByVal ServerIpAddress As String, _
                                                        ByVal SubnetAddress As Long, _
                                                        ByRef  ResumeHandle As Integer, _
                                                        ByRef PreferredMaximum As Integer, _
                                                        ByRef ClientInfo As Integer, _
                                                        ByRef ClientsRead As Integer, _
                                                        ByRef ClientsTotal As Integer) As Integer

The field SubnetAddress is supose to be a Long, but the decimal value for the my Subnet is actualy a double.The subnet address 255.255.255.0 decimal value is 4294967040# wich is a double not a long.
But if I change on the function the SubnetAdress data type to double I receive runtime error 49 'Bad  DLL Calling Convention'.
I've tried to change the field data type to "byVal SubnetAddress as Any" and pass the value as a string but then the function returns no values.
Can somenone help me with this?

Best Regards
JC
JMFCAMPOSAsked:
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TimYatesCommented:
>> wich is a double not a long

Doesn't it work if you just send it as a Long?

0xFFFFFF00 as a signed 32bit number = -256, not 4294967040

Tim
JMFCAMPOSAuthor Commented:
Hi Tim.
Ok! Now the error is gone, but the function returns no values.
I used both the values for the SubnetMaskID field but the result is the same: no entries returned by the function.

    vServerIP = "200.0.1.2"
    pt = 0
    Rem_Handle = 0
    Read_Clients=0
    Total_Clients=0
    vSubNetIp=&HFFFFFF00 '255.255.255.0
    X = DhcpEnumSubnetClients(vServerIP, &HFFFFFF00, Rem_Handle, 32767, pt, Read_Clients, Total_Clients)
   
   vSubNetIp=256
    X = DhcpEnumSubnetClients(vServerIP, 256, Rem_Handle, 32767, pt, Read_Clients, Total_Clients)

Any clue?

Best Regards
JC
TimYatesCommented:
   vSubNetIp=256

should be:

    vSubNetIp = -256

(afaik) :-/
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JMFCAMPOSAuthor Commented:
I 've tried. The function returns no values with -256.
TimYatesCommented:
Hmmm....I'm all out of ideas I'm afraid...hopefully someone else will be able to give you a solution :-(

Sorry I couldn't help...

Good luck!

Tim
JMFCAMPOSAuthor Commented:
Hi there.
I've quit the idea of using the API function dhcpenumsubnetclients, it just d'ont works.
So I have to use DHCPCMD.exe.
I execute the following command line in a batch file on a hidden window using Shellexecute:  "dhcpcmd netAddress enumclients DHCPserverAddress > Result.txt".
The file Result.txt contains the list of the DHCP leases.

Thank's anyway for all the help.
TimYatesCommented:
Cool!  Really glad you got it sorted out, and sorry I couldn't help more :-(

If you post a question here:  http://www.experts-exchange.com/Community_Support/  for 0 points, you can get your points back, and this question added to the "Answered Questions" list, as I'm sure it will help someone in the future :-)

Good skills!

And Good luck!!

Tim
moduloCommented:
Closed, 250 points refunded.
modulo
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