Attribute VB_Name = "Windows"

' Copyright (C) 2011 Eric Ehlers
'
' This file is part of QuantLib, a free-software/open-source library
' for financial quantitative analysts and developers - http://quantlib.org/
'
' QuantLib is free software: you can redistribute it and/or modify it
' under the terms of the QuantLib license.  You should have received a
' copy of the license along with this program; if not, please email
' <quantlib-dev@lists.sf.net>. The license is also available online at
' <http://quantlib.org/license.shtml>.
'
' This program is distributed in the hope that it will be useful, but WITHOUT
' ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
' FOR A PARTICULAR PURPOSE.  See the license for more details.

Option Explicit

'-------------- For Versions Previous to Excel 2010 --------------------
'Declare Function WNetGetUser Lib "mpr.dll" _
'    Alias "WNetGetUserA" (ByVal name As String, _
'    ByVal userName As String, bufLen As Long) As Long

'-------------- For Versions After and Including Excel 2010 --------------------
Declare PtrSafe Function WNetGetUser Lib "mpr.dll" _
    Alias "WNetGetUserA" (ByVal name As String, _
    ByVal userName As String, bufLen As Long) As Long

Function getUserName() As String

   Const bufLen As Integer = 255

   Dim status As Integer
   Dim name, userName As String

   userName = Space$(bufLen + 1)
   status = WNetGetUser(name, userName, bufLen)

   If 0 = status Then
      ' This line removes the null character. Strings in C are null-
      ' terminated. Strings in Visual Basic are not null-terminated.
      ' The null character must be removed from the C strings to be used
      ' cleanly in Visual Basic.
      getUserName = Left$(userName, InStr(userName, Chr(0)) - 1)
   Else
        Call raiseError("Unable to derive windows login ID")
   End If

End Function