imaginad que ejecutamos un comando en una ventana dos. Por ejemplo 'powercfg /list'

existe alguna manera programáticamente de saber que el comando se ha terminado de ejecutar ? O sea, que el sistema ha terminado de ejecutar dicho comando.

He intentado waiforsingleoject sin éxito.

http://stackoverflow.com/questions/5685972/how-to-wait-for-a-shell-process-to-finish-before-executing-further-code-in-vb6

Tenes que usar el waitforsingleobject tienes que asegurarte que el proceso no se interrumpe en ningun momento (ej: que no aparezca el "presione una tecla para continuar...")

Encontre esto en mi biblioteca de codigos

Private Const SW_HIDE = 0
Private Const WAIT_TIMEOUT = &H102
Private Declare Function ShellExecuteExA Lib "shell32" (lpExecInfo As SHELLEXECUTEINFO) As Long
Private Declare Function WaitForSingleObject Lib "kernel32" (ByVal hHandle As Long, ByVal dwMilliseconds As Long) As Long
 
Private Type SHELLEXECUTEINFO
  cbSize As Long
  fMask As Long
  hwnd As Long
  lpVerb As String
  lpFile As String
  lpParameters As String
  lpDirectory As String
  nShow As Long
  hInstApp As Long
  lpIDList As Long
  lpClass As String
  hkeyClass As Long
  dwHotKey As Long
  hIcon As Long
  hProcess As Long
End Type
 
Public Sub ShellWait(ByVal sFile As String, ByVal sParams As String, ByVal sDir As String)
    Dim Retval As Long, ShExInfo As SHELLEXECUTEINFO
    With ShExInfo
        .cbSize = Len(ShExInfo)
        .fMask = 0
        .hwnd = 0
        .lpVerb = "open"
        .lpFile = sFile
        .lpParameters = sParams
        .lpDirectory = sDir
        .nShow = SW_HIDE
    End With
 
    Retval = ShellExecuteExA(ShExInfo)
    If Retval = 0 Then
        Call MsgBox("Error :(")
    Else
        Do
            DoEvents
        Loop Until WaitForSingleObject(ShExInfo.hProcess, 0) < WAIT_TIMEOUT
    End If
End Sub