Wait for Shell to finish, then format cells - synchronously execute a command

Question

I have an executable that I call using the shell command:

Shell (ThisWorkbook.Path & "\ProcessData.exe")

The executable does some computations, then exports results back to Excel. I want to be able to change the format of the results AFTER they are exported.

In other words, i need the Shell command first to WAIT until the executable finishes its task, exports the data, and THEN do the next commands to format.

I tried the Shellandwait(), but without much luck.

I had:

Sub Test()

ShellandWait (ThisWorkbook.Path & "\ProcessData.exe")

'Additional lines to format cells as needed

End Sub

Unfortunately, still, formatting takes place first before the executable finishes.

Just for reference, here was my full code using ShellandWait

' Start the indicated program and wait for it
' to finish, hiding while we wait.


Private Declare Function CloseHandle Lib "kernel32.dll" (ByVal hObject As Long) As Long
Private Declare Function WaitForSingleObject Lib "kernel32.dll" (ByVal hHandle As Long, ByVal dwMilliseconds As Long) As Long
Private Declare Function OpenProcess Lib "kernel32.dll" (ByVal dwDesiredAccessas As Long, ByVal bInheritHandle As Long, ByVal dwProcId As Long) As Long
Private Const INFINITE = &HFFFF


Private Sub ShellAndWait(ByVal program_name As String)
Dim process_id As Long
Dim process_handle As Long

' Start the program.
On Error GoTo ShellError
process_id = Shell(program_name)
On Error GoTo 0

' Wait for the program to finish.
' Get the process handle.
process_handle = OpenProcess(SYNCHRONIZE, 0, process_id)
If process_handle <> 0 Then
WaitForSingleObject process_handle, INFINITE
CloseHandle process_handle
End If

Exit Sub

ShellError:
MsgBox "Error starting task " & _
txtProgram.Text & vbCrLf & _
Err.Description, vbOKOnly Or vbExclamation, _
"Error"

End Sub

Sub ProcessData()

  ShellAndWait (ThisWorkbook.Path & "\Datacleanup.exe")

  Range("A2").Select
    Range(Selection, Selection.End(xlToRight)).Select
    Range(Selection, Selection.End(xlDown)).Select
    With Selection
        .HorizontalAlignment = xlLeft
        .VerticalAlignment = xlTop
        .WrapText = True
        .Orientation = 0
        .AddIndent = False
        .IndentLevel = 0
        .ShrinkToFit = False
        .ReadingOrder = xlContext
        .MergeCells = False
    End With
    Selection.Borders(xlDiagonalDown).LineStyle = xlNone
    Selection.Borders(xlDiagonalUp).LineStyle = xlNone
End Sub

Answer 1

Try the WshShell object instead of the native Shell function.

Dim wsh As Object
Set wsh = VBA.CreateObject("WScript.Shell")
Dim waitOnReturn As Boolean: waitOnReturn = True
Dim windowStyle As Integer: windowStyle = 1
Dim errorCode As Long

errorCode = wsh.Run("notepad.exe", windowStyle, waitOnReturn)

If errorCode = 0 Then
    MsgBox "Done! No error to report."
Else
    MsgBox "Program exited with error code " & errorCode & "."
End If    

Though note that:

If bWaitOnReturn is set to false (the default), the Run method returns immediately after starting the program, automatically returning 0 (not to be interpreted as an error code).

So to detect whether the program executed successfully, you need waitOnReturn to be set to True as in my example above. Otherwise it will just return zero no matter what.

For early binding (gives access to Autocompletion), set a reference to "Windows Script Host Object Model" (Tools > Reference > set checkmark) and declare like this:

Dim wsh As WshShell 
Set wsh = New WshShell

Now to run your process instead of Notepad... I expect your system will balk at paths containing space characters (...\My Documents\..., ...\Program Files\..., etc.), so you should enclose the path in "quotes":

Dim pth as String
pth = """" & ThisWorkbook.Path & "\ProcessData.exe" & """"
errorCode = wsh.Run(pth , windowStyle, waitOnReturn)

Answer 2

What you have will work once you add

Private Const SYNCHRONIZE = &H100000

which your missing. (Meaning 0 is being passed as the access right to OpenProcess which is not valid)

Making Option Explicit the top line of all your modules would have raised an error in this case

Answer 3

Shell-and-Wait in VBA _{^{(Compact Edition)}}

Sub ShellAndWait(pathFile As String)
    With CreateObject("WScript.Shell")
        .Run pathFile, 1, True
    End With
End Sub

---

Example Usage:

Sub demo_Wait()
    ShellAndWait ("notepad.exe")
    Beep 'this won't run until Notepad window is closed
    MsgBox "Done!"
End Sub

---

Adapted from (and more options at) Chip Pearson's site.

Answer 4

The WScript.Shell object's .Run() method as demonstrated in Jean-François Corbett's helpful answer is the right choice if you know that the command you invoke will finish in the expected time frame.

Below is SyncShell(), an alternative that allows you to specify a timeout, inspired by the great ShellAndWait() implementation. (The latter is a bit heavy-handed and sometimes a leaner alternative is preferable.)

' Windows API function declarations.
Private Declare Function OpenProcess Lib "kernel32.dll" (ByVal dwDesiredAccessas As Long, ByVal bInheritHandle As Long, ByVal dwProcId As Long) As Long
Private Declare Function CloseHandle Lib "kernel32.dll" (ByVal hObject As Long) As Long
Private Declare Function WaitForSingleObject Lib "kernel32.dll" (ByVal hHandle As Long, ByVal dwMilliseconds As Long) As Long
Private Declare Function GetExitCodeProcess Lib "kernel32.dll" (ByVal hProcess As Long, ByRef lpExitCodeOut As Long) As Integer

' Synchronously executes the specified command and returns its exit code.
' Waits indefinitely for the command to finish, unless you pass a 
' timeout value in seconds for `timeoutInSecs`.
Private Function SyncShell(ByVal cmd As String, _
                           Optional ByVal windowStyle As VbAppWinStyle = vbMinimizedFocus, _
                           Optional ByVal timeoutInSecs As Double = -1) As Long

    Dim pid As Long ' PID (process ID) as returned by Shell().
    Dim h As Long ' Process handle
    Dim sts As Long ' WinAPI return value
    Dim timeoutMs As Long ' WINAPI timeout value
    Dim exitCode As Long

    ' Invoke the command (invariably asynchronously) and store the PID returned.
    ' Note that this invocation may raise an error.
    pid = Shell(cmd, windowStyle)

    ' Translate the PIP into a process *handle* with the
    ' SYNCHRONIZE and PROCESS_QUERY_LIMITED_INFORMATION access rights,
    ' so we can wait for the process to terminate and query its exit code.
    ' &H100000 == SYNCHRONIZE, &H1000 == PROCESS_QUERY_LIMITED_INFORMATION
    h = OpenProcess(&H100000 Or &H1000, 0, pid)
    If h = 0 Then
        Err.Raise vbObjectError + 1024, , _
          "Failed to obtain process handle for process with ID " & pid & "."
    End If

    ' Now wait for the process to terminate.
    If timeoutInSecs = -1 Then
        timeoutMs = &HFFFF ' INFINITE
    Else
        timeoutMs = timeoutInSecs * 1000
    End If
    sts = WaitForSingleObject(h, timeoutMs)
    If sts <> 0 Then
        Err.Raise vbObjectError + 1025, , _
         "Waiting for process with ID " & pid & _
         " to terminate timed out, or an unexpected error occurred."
    End If

    ' Obtain the process's exit code.
    sts = GetExitCodeProcess(h, exitCode) ' Return value is a BOOL: 1 for true, 0 for false
    If sts <> 1 Then
        Err.Raise vbObjectError + 1026, , _
          "Failed to obtain exit code for process ID " & pid & "."
    End If

    CloseHandle h

    ' Return the exit code.
    SyncShell = exitCode

End Function

' Example
Sub Main()

    Dim cmd As String
    Dim exitCode As Long

    cmd = "Notepad"

    ' Synchronously invoke the command and wait
    ' at most 5 seconds for it to terminate.
    exitCode = SyncShell(cmd, vbNormalFocus, 5)

    MsgBox "'" & cmd & "' finished with exit code " & exitCode & ".", vbInformation


End Sub

Answer 5

Simpler and Compressed Code with examples:

first declare your path

Dim path: path = ThisWorkbook.Path & "\ProcessData.exe"

And then use any one line of following code you like


1) Shown + waited + exited

VBA.CreateObject("WScript.Shell").Run path,1, True 

2) Hidden + waited + exited

VBA.CreateObject("WScript.Shell").Run path,0, True

3) Shown + No waited

VBA.CreateObject("WScript.Shell").Run path,1, False

4) Hidden + No waited

VBA.CreateObject("WScript.Shell").Run path,0, False

Answer 6

I was looking for a simple solution too and finally ended up to make these two functions, so maybe for future enthusiast readers :)

1.) prog must be running, reads tasklist from dos, output status to file, read file in vba

2.) start prog and wait till prog is closed with a wscript shell .exec waitonrun

3.) ask for confirmation to delete tmp file

Modify program name and path variables and run in one go.

Sub dosWOR_caller()

    Dim pwatch As String, ppath As String, pfull As String
    pwatch = "vlc.exe"                                      'process to watch, or process.exe (do NOT use on cmd.exe itself...)
    ppath = "C:\Program Files\VideoLAN\VLC"                 'path to the program, or ThisWorkbook.Path
    pfull = ppath & "\" & pwatch                            'extra quotes in cmd line

    Dim fout As String                                      'tmp file for r/w status in 1)
    fout = Environ("userprofile") & "\Desktop\dosWaitOnRun_log.txt"

    Dim status As Boolean, t As Double
    status = False

    '1) wait until done

    t = Timer
    If Not status Then Debug.Print "run prog first for this one! then close it to stop dosWORrun ": Shell (pfull)
    status = dosWORrun(pwatch, fout)
    If status Then Debug.Print "elapsed time: "; Format(Timer - t, "#.00s")

    '2) wait while running

    t = Timer
    Debug.Print "now running the prog and waiting you close it..."
    status = dosWORexec(pfull)
    If status = True Then Debug.Print "elapsed time: "; Format(Timer - t, "#.00s")

    '3) or if you need user action

    With CreateObject("wScript.Shell")
        .Run "cmd.exe /c title=.:The end:. & set /p""=Just press [enter] to delete tmp file"" & del " & fout & " & set/p""=and again to quit ;)""", 1, True
    End With

End Sub

Function dosWORrun(pwatch As String, fout As String) As Boolean
'redirect sdtout to file, then read status and loop

    Dim i As Long, scatch() As String

    dosWORrun = False

    If pwatch = "cmd.exe" Then Exit Function

    With CreateObject("wScript.Shell")
        Do
            i = i + 1

            .Run "cmd /c >""" & fout & """ (tasklist |find """ & pwatch & """ >nul && echo.""still running""|| echo.""done"")", 0, True

            scatch = fReadb(fout)

            Debug.Print i; scatch(0)

        Loop Until scatch(0) = """done"""
    End With

    dosWORrun = True
End Function

Function dosWORexec(pwatch As String) As Boolean
'the trick: with .exec method, use .stdout.readall of the WshlExec object to force vba to wait too!

    Dim scatch() As String, y As Object

    dosWORexec = False

    With CreateObject("wScript.Shell")

        Set y = .exec("cmd.exe /k """ & pwatch & """ & exit")

        scatch = Split(y.stdout.readall, vbNewLine)

        Debug.Print y.status
        Set y = Nothing
    End With

    dosWORexec = True
End Function

Function fReadb(txtfile As String) As String()
'fast read

    Dim ff As Long, data As String

    '~~. Open as txt File and read it in one go into memory
    ff = FreeFile
    Open txtfile For Binary As #ff
    data = Space$(LOF(1))
    Get #ff, , data
    Close #ff

    '~~> Store content in array
    fReadb = Split(data, vbCrLf)

    '~~ skip last crlf
    If UBound(fReadb) <> -1 Then ReDim Preserve fReadb(0 To UBound(fReadb) - 1)
End Function

Answer 7

I incorporated this into a routine, and it has worked fine (but not used very often) for several years - for which, many thanks !

But now I find it throws up an error :- Run-time error '-2147024894 (80070002)': Method 'Run' of object 'IWshSheB' failed

on the line - ErrorCode = wsh.Run(myCommand, windowStyle, WaitOnReturn)

Very strange !

---

5 hours later !

I THINK the reason it fails is that dear MicroSoft ("dear" meaning expensive) has changed something radical - "Shell" USED to be "Shell to DOS", but has that been changed >=? The "Command" that I want the Shell to run is simply DIR In full, it is "DIR C:\Folder\ /S >myFIle.txt"

. . . . . . . . . . . . . . . . . . . . . .

An hour after that- Yup ! I have "solved" it by using this Code, which works just fine :-

    Sub ShellAndWait(PathFile As String, _
                     Optional Wait As Boolean = True, _
                     Optional Hidden As Boolean = True)
    ' Hidden = 0; Shown = 1
    Dim Hash As Integer, myBat As String, Shown As Integer
    Shown = 0
    If Hidden Then Shown = 1
    If Hidden <> 0 Then Hidden = 1
    Hash = FreeFile
    
    myBat = "C:\Users\Public\myBat.bat"
    
    Open myBat For Output As #Hash
    Print #Hash, PathFile
    Close #Hash
    
        With CreateObject("WScript.Shell")
            .Run myBat, Shown, Wait
        End With
    End Sub

Answer 8

I would come at this by using the Timer function. Figure out roughly how long you'd like the macro to pause while the .exe does its thing, and then change the '10' in the commented line to whatever time (in seconds) that you'd like.

Strt = Timer
Shell (ThisWorkbook.Path & "\ProcessData.exe")  
Do While Timer < Strt + 10     'This line loops the code for 10 seconds
Loop 
UserForm2.Hide 

'Additional lines to set formatting

This should do the trick, let me know if not.

Cheers, Ben.