Loop until end

[mdn29]

I have this piece of code.

ShellExecute Me.hwnd, vbNullString, "c:\mybat.bat", _
vbNullString, "C:\", SW_SHOWNORMAL

I want this to loop until it has ended.

Any ideas ?

[vbud]

hmmm...I think you need to shell the application and wait till it has finished. I've used some code before to do that and it works pretty fine without any noticeably memory leaks.

Try this:

Option Explicit
 
Private Type STARTUPINFO
  cb As Long
  lpReserved As String
  lpDesktop As String
  lpTitle As String
  dwX As Long
  dwY As Long
  dwXSize As Long
  dwYSize As Long
  dwXCountChars As Long
  dwYCountChars As Long
  dwFillAttribute As Long
  dwFlags As Long
  wShowWindow As Integer
  cbReserved2 As Integer
  lpReserved2 As Long
  hStdInput As Long
  hStdOutput As Long
  hStdError As Long
End Type
 
Private Type PROCESS_INFORMATION
  hProcess     As Long
  hThread      As Long
  dwProcessId  As Long
  dwThreadID   As Long
End Type
 
Private Type SECURITY_ATTRIBUTES
  nLength               As Long
  lpSecurityDescriptor  As Long
  bInheritHandle        As Long
End Type
 
Private Declare Function WaitForSingleObject Lib "kernel32" (ByVal _
                           hHandle As Long, ByVal dwMilliseconds As Long) As Long
 
Private Declare Function CreateProcess Lib "kernel32" Alias "CreateProcessA" _
                          (ByVal lpApplicationName As String, _
                           ByVal lpCommandLine As String, _
                           lpProcessAttributes As SECURITY_ATTRIBUTES, _
                           lpThreadAttributes As SECURITY_ATTRIBUTES, _
                           ByVal bInheritHandles As Long, _
                           ByVal dwCreationFlags As Long, _
                           lpEnvironment As Any, _
                           ByVal lpCurrentDirectory As String, _
                           lpStartupInfo As STARTUPINFO, _
                           lpProcessInformation As PROCESS_INFORMATION) As Long
 
Private Declare Function TerminateProcess Lib "kernel32" (ByVal hProcess As Long, _
                            ByVal uExitCode As Long) As Long
 
Private Declare Function CreatePipe Lib "kernel32" (phReadPipe As Long, _
                          phWritePipe As Long, lpPipeAttributes As SECURITY_ATTRIBUTES, _
                          ByVal nSize As Long) As Long
 
Private Declare Function CloseHandle Lib "kernel32" _
                          (ByVal hObject As Long) As Long
 
Private Declare Function GetExitCodeProcess Lib "kernel32" _
                          (ByVal hProcess As Long, lpExitCode As Long) As Long
 
Private Const STARTF_USESTDHANDLES As Long = &H100&
Private Const STARTF_USESHOWWINDOW As Long = &H1&
 
Private Const SW_HIDE As Long = 0&
Private Const SW_SHOWNORMAL = 1
Private Const SW_SHOWMINIMIZED = 2
Private Const SW_SHOWMAXIMIZED = 3
Private Const SW_SHOWNOACTIVATE = 4
Private Const SW_SHOW = 5
Private Const SW_MINIMIZE = 6
Private Const SW_SHOWMINNOACTIVE = 7
Private Const SW_SHOWNA = 8
Private Const SW_RESTORE = 9
 
Private Const WAIT_ABANDONED = &H80
Private Const WAIT_FAILED = &HFFFFFFFF
Private Const WAIT_OBJECT_O = &H0
Private Const WAIT_TIMEOUT = &H102
 
Private Const NORMAL_PRIORITY_CLASS = &H20
Private Const INFINITE = -1&
 
Private Sub RunCommand(ByVal lcStrCommandLine As String)
  
  Dim ProcInfo            As PROCESS_INFORMATION
  Dim startinfo           As STARTUPINFO
  Dim lcLngRetVal         As Long
  Dim retval              As Long
  Dim SA                  As SECURITY_ATTRIBUTES
  Dim hRead               As Long 'the handle to the read end of the pipe
  Dim hWrite              As Long 'the handle to the write end of the pipe
  Dim lcStrErrPrefix      As String
  Dim lcStrErrMsg         As String
    
  On Error GoTo ErrHandler
    
  'set up security attributes structure
  With SA
    .nLength = Len(SA)
    .bInheritHandle = 1& 'inherit, needed for this to work
    .lpSecurityDescriptor = 0&
  End With
  
  'create our anonymous pipe an check for success
  retval = CreatePipe(hRead, hWrite, SA, 0&)
  If retval = 0 Then
    Debug.Print "CreatePipe Failed"
    Exit Sub
  End If
 
  ' Initialize the STARTUPINFO structure:
  With startinfo
    .cb = Len(startinfo)
    .dwFlags = STARTF_USESTDHANDLES Or STARTF_USESHOWWINDOW
    .wShowWindow = SW_HIDE
    .hStdOutput = hWrite
    .wShowWindow = SW_HIDE
  End With
  
  ' Start the shelled application:
  lcLngRetVal = CreateProcess(vbNullString, Chr(34) & lcStrCommandLine & Chr(34), SA, SA, 1&, _
                NORMAL_PRIORITY_CLASS, 0&, vbNullString, startinfo, ProcInfo)
 
  If lcLngRetVal = 0 Then
    lcStrErrMsg = "Could not execute the DOS command: " & lcStrCommandLine
    Debug.Print lcStrErrMsg
    Exit Sub
  End If
 
  ' Wait for the shelled application to finish:
  If WaitForSingleObject(ProcInfo.hProcess, INFINITE) <> WAIT_OBJECT_O Then
    TerminateProcess ProcInfo.hProcess, 0
    TerminateProcess ProcInfo.hThread, 0
  End If
  
  Call CloseHandle(ProcInfo.hProcess)
  Call CloseHandle(ProcInfo.hThread)
  Debug.Print "Process Terminated"
 
  Exit Sub
  
ErrHandler:
  Debug.Print Err.Description
End Sub

usage:

call RunCommand "c:\mybat.bat"