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Private Const NCBASTAT As Long = &H33
Private Const NCBNAMSZ As Long = 16
Private Const HEAP_ZERO_MEMORY As Long = &H8
Private Const NCBRESET As Long = &H32
ncb_command    As Byte
ncb_retcode    As Byte
ncb_lsn        As Byte
ncb_num        As Byte
ncb_buffer     As Long
ncb_length     As Integer
ncb_callname As String * NCBNAMSZ
ncb_name     As String * NCBNAMSZ
ncb_rto        As Byte
ncb_sto        As Byte
ncb_post     As Long
ncb_lana_num As Byte
ncb_cmd_cplt As Byte
ncb_reserve(9) As Byte ' Reserved, must be 0
ncb_event     As Long
End Type
adapter_address(5) As Byte
rev_major         As Byte
reserved0         As Byte
adapter_type     As Byte
rev_minor         As Byte
duration         As Integer
frmr_recv         As Integer
frmr_xmit         As Integer
iframe_recv_err As Integer
xmit_aborts     As Integer
xmit_success     As Long
recv_success     As Long
iframe_xmit_err As Integer
recv_buff_unavail As Integer
t1_timeouts     As Integer
ti_timeouts     As Integer
Reserved1         As Long
free_ncbs         As Integer
max_cfg_ncbs     As Integer
max_ncbs         As Integer
xmit_buf_unavail As Integer
max_dgram_size    As Integer
pending_sess     As Integer
max_cfg_sess     As Integer
max_sess         As Integer
max_sess_pkt_size As Integer
name_count        As Integer
End Type
Private Type NAME_BUFFER
name        As String * NCBNAMSZ
name_num    As Integer
name_flags As Integer
End Type
Private Type ASTAT
adapt         As ADAPTER_STATUS
NameBuff(30) As NAME_BUFFER
End Type
Private Declare Function Netbios Lib "netapi32.dll" (pncb As NET_CONTROL_BLOCK) As Byte
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (hpvDest As Any, ByVal hpvSource As Long, ByVal cbCopy As Long)
Private Declare Function GetProcessHeap Lib "kernel32" () As Long
Private Declare Function HeapAlloc Lib "kernel32" (ByVal hHeap As Long, ByVal dwFlags As Long, ByVal dwBytes As Long) As Long
Private Declare Function HeapFree Lib "kernel32" (ByVal hHeap As Long, ByVal dwFlags As Long, lpMem As Any) As Long
Function GetMACAddress() As String
'retrieve the MAC Address for the network controller
'installed, returning a formatted string
Dim tmp As String
Dim pASTAT As Long
'The IBM NetBIOS 3.0 specifications defines four basic
'NetBIOS environments under the NCBRESET command. Win32
'follows the OS/2 Dynamic Link Routine (DLR) environment.
'This means that the first NCB issued by an application
'must be a NCBRESET, with the exception of NCBENUM.
'The Windows NT implementation differs from the IBM
'NetBIOS 3.0 specifications in the NCB_CALLNAME field.
NCB.ncb_command = NCBRESET
Call Netbios(NCB)
'To get the Media Access Control (MAC) address for an
'ethernet adapter programmatically, use the Netbios()
'NCBASTAT command and provide a "*" as the name in the
'NCB.ncb_CallName field (in a 16-chr string).
NCB.ncb_callname = "*             "
NCB.ncb_command = NCBASTAT
'For machines with multiple network adapters you need to
'enumerate the LANA numbers and perform the NCBASTAT
'command on each. Even when you have a single network
'adapter, it is a good idea to enumerate valid LANA numbers
'first and perform the NCBASTAT on one of the valid LANA
'numbers. It is considered bad programming to hardcode the
'LANA number to 0 (see the comments section below).
NCB.ncb_lana_num = 0
NCB.ncb_length = Len(AST)
If pASTAT = 0 Then
     Debug.Print "memory allocation failed!"
     Exit Function
End If
NCB.ncb_buffer = pASTAT
Call Netbios(NCB)
CopyMemory AST, NCB.ncb_buffer, Len(AST)
tmp = Format$(Hex(AST.adapt.adapter_address(0)), "00") & " " & Format$(Hex(AST.adapt.adapter_address(1)), "00") & " " & Format$(Hex(AST.adapt.adapter_address(2)), "00") & " " & Format$(Hex(AST.adapt.adapter_address(3)), "00") & " " & Format$(Hex(AST.adapt.adapter_address(4)), "00") & " " & Format$(Hex(AST.adapt.adapter_address(5)), "00")
HeapFree GetProcessHeap(), 0, pASTAT
GetMACAddress = tmp
End Function
Private Sub Form_Load()
'KPD-Team 2000
' -> Source: MS Knowledge Base
MsgBox "Network adapter address: " + GetMACAddress()
End Sub

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