C# Signature:

[DllImport("advapi32.dll", CharSet=CharSet.Auto)]
static extern uint SetNamedSecurityInfo(
    string pObjectName,
    SE_OBJECT_TYPE ObjectType,
    SECURITY_INFORMATION SecurityInfo,
    IntPtr psidOwner,
    IntPtr psidGroup,
    IntPtr pDacl,
    IntPtr pSacl);

VB Signature:

Declare Function SetNamedSecurityInfo Lib "advapi32.dll" ( _
    ByVal pObjectName As String, _
    ByVal ObjectType As SE_OBJECT_TYPE, _
    ByVal SecurityInfo As SECURITY_INFORMATION, _
    ByVal psidOwner As IntPtr, _
    ByVal psidGroup As IntPtr, _
    ByVal pDacl As IntPtr, _
    ByVal pSacl As IntPtr) As Integer

User-Defined Types:

None.

Notes:

Tips & Tricks:

Please add some!

C# Sample Code:

Please add some!

VB.Net Sample Code:

Dim pSecDesc, pNewDACL, pOldDACL As IntPtr
Dim ea As EXPLICIT_ACCESS
Dim Win32Error As Win32Exception
Dim ret As Integer

' merge this Explict Access with the existing DACL
ret = SetEntriesInAcl(1, ea, pOldDACL, pNewDACL)
If ret <> 0 Then
     Win32Error = New Win32Exception(ret)
     Throw New Exception(Win32Error.Message)
End If

' write the new Security Descriptor/DACL back
ret = SetNamedSecurityInfo(strPath, _
     SE_OBJECT_TYPE.SE_FILE_OBJECT, _
     SECURITY_INFORMATION.DACL_SECURITY_INFORMATION, _
     Nothing, Nothing, pNewDACL, Nothing)
If ret <> 0 Then
     Win32Error = New Win32Exception(ret)
     Throw New Exception(Win32Error.Message)
End If

Alternative Managed API:

Do you know one? Please contribute it!