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Imports Microsoft.Win32.SafeHandles
Imports System.IO
 
Module Module_ADS ' Alternate Data Streams
    Private Const GENERIC_ALL As Int32 = &H10000000   ' not used
    Private Const GENERIC_EXECUTE As Int32 = &H20000000  ' not used
    Private Const GENERIC_WRITE As Int32 = &H40000000
    Private Const GENERIC_READ As Int32 = &H80000000
 
    Private Const FILE_SHARE_NONE As Int32 = &H0         ' not used
    Private Const FILE_SHARE_READ As Int32 = &H1
    Private Const FILE_SHARE_WRITE As Int32 = &H2
    Private Const FILE_SHARE_DELETE As Int32 = &H4     ' not used
 
    Private Const CREATE_NEW As Int32 = 1               ' not used
    Private Const CREATE_ALWAYS As Int32 = 2             ' not used
    Private Const OPEN_EXISTING As Int32 = 3
    Private Const OPEN_ALWAYS As Int32 = 4
 
    Private Const FILE_ATTRIBUTE_NORMAL = &H80
    Private Const FILE_FLAG_NO_BUFFERING = &H20000000   ' not used
    Private Structure SECURITY_ATTRIBUTES
        Dim nLength As Int32
        Dim lpSecurityDescriptor As IntPtr
        Dim bInheritHandle As Boolean
    End Structure
    Private Declare Auto Function CreateFile Lib "kernel32.dll" ( _
        ByVal lpFileName As String, _
        ByVal dwDesiredAccess As Int32, _
        ByVal dwShareMode As Int32, _
        ByRef lpSecurityAttributes As SECURITY_ATTRIBUTES, _
        ByVal dwCreationDistribution As Int32, _
        ByVal dwFlagsAndAttributes As Int32, _
        ByVal hTemplateFile As IntPtr _
        ) As SafeFileHandle
 
    Public Function ADSExits(ByVal FileName As String, ByVal ADSName As String) As Boolean
        Dim sa As New SECURITY_ATTRIBUTES
        sa.nLength = 0
        sa.lpSecurityDescriptor = 0
        sa.bInheritHandle = False
        Return Not CreateFile(FileName + ":" + ADSName, GENERIC_READ Or GENERIC_WRITE, FILE_SHARE_READ Or FILE_SHARE_WRITE, sa, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0).IsInvalid
    End Function
    Public Function GetADSHandle(ByVal FileName As String, ByVal ADSName As String) As SafeFileHandle
        Dim sa As New SECURITY_ATTRIBUTES
        sa.nLength = 0
        sa.lpSecurityDescriptor = 0
        sa.bInheritHandle = False
        Return CreateFile(FileName + ":" + ADSName, GENERIC_READ Or GENERIC_WRITE, FILE_SHARE_READ Or FILE_SHARE_WRITE, sa, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, 0)
    End Function
End Module