Why it doe'nt reboot?

[sebs]

I want my program to reboot my computer and my code:

Private Sub Command1_Click()
Dim retval As Long  ' return value
retval = ExitWindowsEx(EWX_FORCE Or EWX_REBOOT, 0)
End Sub

my module:

Public Declare Function ExitWindowsEx Lib "user32.dll" 
(ByVal uFlags As Long, ByVal dwReserved As Long) As Long

i try it with a look up
and my return value(retval) = 1, so it's suppose to reboot but it's not, WHY????????

[hitcgar]

What OS are you running?

If NT or 2000 you may have to use the

Public Declare Function AdjustTokenPrivileges Lib "advapi32.dll" Alias "AdjustTokenPrivileges" _
(ByVal TokenHandle As Long, _
ByVal DisableAllPrivileges As Long, _
NewState As TOKEN_PRIVILEGES, _
ByVal BufferLength As Long, _
PreviousState As TOKEN_PRIVILEGES, _
ReturnLength As Long) As Long

function to enable the necessary privileges so that your app can do a shutdown.

An example in C from MSDN:

HANDLE hToken; 
TOKEN_PRIVILEGES tkp; 
 
// Get a token for this process. 
 
if (!OpenProcessToken(GetCurrentProcess(), 
        TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY, &hToken)) 
    error("OpenProcessToken"); 
 
// Get the LUID for the shutdown privilege. 
 
LookupPrivilegeValue(NULL, SE_SHUTDOWN_NAME, 
        &tkp.Privileges[0].Luid); 
 
tkp.PrivilegeCount = 1;  // one privilege to set    
tkp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED; 
 
// Get the shutdown privilege for this process. 
 
AdjustTokenPrivileges(hToken, FALSE, &tkp, 0, 
        (PTOKEN_PRIVILEGES)NULL, 0); 
 
// Cannot test the return value of AdjustTokenPrivileges. 
 
if (GetLastError() != ERROR_SUCCESS) 
    error("AdjustTokenPrivileges"); 
 
// Shut down the system and force all applications to close. 
 
if (!ExitWindowsEx(EWX_SHUTDOWN | EWX_FORCE, 0)) 
    error("ExitWindowsEx");

Check here also.
Your process must have the SE_SHUTDOWN_NAME privilege for this on NT/2000.

hope it helps 'cause otherwise I can't tell you why the function wouldn't execute properly while returning 1.

[sebs]

I'm with NT:

Do you have an example in VB

[Frans C]

This should work on NT 4 and 5.

Option Explicit

Private Type LUID
    UsedPart As Long
    IgnoredForNowHigh32BitPart As Long
End Type
Private Type TOKEN_PRIVILEGES
    PrivilegeCount As Long
    TheLuid As LUID
    Attributes As Long
End Type

Private Declare Function GetCurrentProcess Lib "kernel32" () As Long
Private Declare Function OpenProcessToken Lib "advapi32" (ByVal ProcessHandle As Long, ByVal DesiredAccess As Long, TokenHandle As Long) As Long
Private Declare Function LookupPrivilegeValue Lib "advapi32" Alias "LookupPrivilegeValueA" (ByVal lpSystemName As String, ByVal lpName As String, lpLuid As LUID) As Long
Private Declare Function AdjustTokenPrivileges Lib "advapi32" (ByVal TokenHandle As Long, ByVal DisableAllPrivileges As Long, NewState As TOKEN_PRIVILEGES, ByVal BufferLength As Long, PreviousState As Long, ReturnLength As Long) As Long
Private Declare Function ExitWindowsEx Lib "user32" (ByVal uFlags As Long, ByVal dwReserved As Long) As Long

Private Const TOKEN_ADJUST_PRIVILEGES = &H20
Private Const TOKEN_QUERY = &H8
Private Const SE_PRIVILEGE_ENABLED = &H2
Private Const EWX_FORCE = 4
Private Const EWX_REBOOT = 2
Private Const SE_SHUTDOWN_NAME = "SeShutdownPrivilege"

Private Sub ShutDown()
Dim retVal As Long
Dim hToken As Long
Dim tmpLuid As LUID
Dim tkp As TOKEN_PRIVILEGES
    
    OpenProcessToken GetCurrentProcess, (TOKEN_ADJUST_PRIVILEGES Or TOKEN_QUERY), hToken
    ' Get the LUID for shutdown privilege
    retVal = LookupPrivilegeValue(vbNullString, SE_SHUTDOWN_NAME, tmpLuid)
    tkp.PrivilegeCount = 1    ' One privilege to set
    tkp.TheLuid = tmpLuid
    tkp.Attributes = SE_PRIVILEGE_ENABLED
    ' Enable the shutdown privilege in the access token of this process
    retVal = AdjustTokenPrivileges(hToken, False, tkp, 0, ByVal 0, 0)
    
    retVal = ExitWindowsEx(EWX_FORCE Or EWX_REBOOT, 0)
End Sub

Private Sub Command1_Click()
    Call ShutDown
End Sub

P.S. Of course it is only possible to enable the shutdown privilege if the user has that privilege. You can't use this function to reboot a pc, if the user is not allowed to reboot his pc.

[Edited by Frans C on 10-11-2000 at 02:59 PM]

[sebs]

Still does'nt work, i dunno why?

And i have the write to reboot/shutdown my computer.

It work if i only force it,but i want to reboot it!!!!

[Frans C]

I also had bad experiences with the ExitWindowsEx function. It didn't work properly on all PC's.

I prefer the RemoteSystemShutdown function. This also allows to reboot another NT workstation on the network (if you have admin rights).

I'll include the full code I used in an app I previously wrote. You need two commandbuttons (cmdShutdown and cmdAbort), three textboxes (txtCompName, txtTimeOut and txtMessage) and two checkboxes (chkReboot and chkForce).

Option Explicit
Private Type LUID
    UsedPart As Long
    IgnoredForNowHigh32BitPart As Long
End Type
Private Type TOKEN_PRIVILEGES
    PrivilegeCount As Long
    TheLuid As LUID
    Attributes As Long
End Type
Private Declare Function InitiateSystemShutdown Lib "advapi32.dll" Alias "InitiateSystemShutdownA" (ByVal lpMachineName As String, ByVal lpMessage As String, ByVal dwTimeout As Long, ByVal bForceAppsClosed As Boolean, ByVal bRebootAfterShutdown As Boolean) As Boolean
'Private Declare Function SetCurrentPrivilege Lib "advapi32.dll" Alias "SetCurrentPrivilegeA" (ByVal TargetComputer As String, ByVal Privilege As String, ByVal bEnablePrivilege As Boolean) As Boolean
Private Declare Function AbortSystemShutdown Lib "advapi32.dll" Alias "AbortSystemShutdownA" (ByVal lpMachineName As String) As Boolean

Private Declare Function GetCurrentProcess Lib "kernel32" () As Long
Private Declare Function OpenProcessToken Lib "advapi32" (ByVal ProcessHandle As Long, ByVal DesiredAccess As Long, TokenHandle As Long) As Long
Private Declare Function LookupPrivilegeValue Lib "advapi32" Alias "LookupPrivilegeValueA" (ByVal lpSystemName As String, ByVal lpName As String, lpLuid As LUID) As Long
Private Declare Function AdjustTokenPrivileges Lib "advapi32" (ByVal TokenHandle As Long, ByVal DisableAllPrivileges As Long, NewState As TOKEN_PRIVILEGES, ByVal BufferLength As Long, PreviousState As TOKEN_PRIVILEGES, ReturnLength As Long) As Long
Private Const TOKEN_ADJUST_PRIVILEGES = &H20
Private Const TOKEN_QUERY = &H8
Private Const SE_PRIVILEGE_ENABLED = &H2

'To shut down the local computer, the calling process must have the SE_SHUTDOWN_NAME privilege. To shut down a remote computer, the calling process must have the SE_REMOTE_SHUTDOWN_NAME privilege on the remote computer. By default, users can enable the SE_SHUTDOWN_NAME privilege on the computer they are logged onto, and administrators can enable the SE_REMOTE_SHUTDOWN_NAME privilege on remote computers.

Private Sub ShutDown(ByVal Abort As Boolean)
Dim lRet As Boolean
Dim CompName As String
Dim Message As String
Dim TimeOut As Long
Dim Force As Boolean
Dim Reboot As Boolean
Dim Privilege As String
Dim hdlProcessHandle As Long
Dim hdlTokenHandle As Long
Dim tmpLuid As LUID
Dim tkp As TOKEN_PRIVILEGES
Dim tkpNewButIgnored As TOKEN_PRIVILEGES
Dim lBufferNeeded As Long
         

    Force = chkForce.Value = vbChecked
    Reboot = chkReboot.Value = vbChecked
    Message = txtMessage.Text
    CompName = txtCompName.Text
    If Len(Trim(CompName)) = 0 Then
        ' no computername specified
        ' so shutdown the local PC
        CompName = vbNullString
        Privilege = "SeShutdownPrivilege"
    Else
        Privilege = "SeRemoteShutdownPrivilege"
    End If
    If IsNumeric(txtTimeOut.Text) Then
        TimeOut = Val(txtTimeOut.Text)
    Else
        TimeOut = 10
    End If
    
    hdlProcessHandle = GetCurrentProcess()
    OpenProcessToken hdlProcessHandle, (TOKEN_ADJUST_PRIVILEGES Or TOKEN_QUERY), hdlTokenHandle
    ' Get the LUID for shutdown privilege
    LookupPrivilegeValue "", Privilege, tmpLuid
    tkp.PrivilegeCount = 1    ' One privilege to set
    tkp.TheLuid = tmpLuid
    tkp.Attributes = SE_PRIVILEGE_ENABLED
    ' Enable the shutdown privilege in the access token of this process
    AdjustTokenPrivileges hdlTokenHandle, False, tkp, Len(tkpNewButIgnored), tkpNewButIgnored, lBufferNeeded
    'lRet = SetCurrentPrivilege(CompName, "SeShutdownPrivilege", True)
    If Abort Then
        lRet = AbortSystemShutdown(CompName)
    Else
        lRet = InitiateSystemShutdown(CompName, Message, TimeOut, Force, Reboot)
    End If

End Sub

Private Sub cmdAbort_Click()
    Call ShutDown(True)
End Sub

Private Sub cmdShutdown_Click()
    Call ShutDown(False)
End Sub