How to Execute shell comands in hidden mode?

[FerdieB]

In Access 2007 help file, a neat piece of coding is supplied on how to
execute shell commands and wait for the shelled application process to finish
before returning to the calling function. It looks bad if a batch file runs
and a flashing window pops up for a split second without any use for the end
user.
Somehow there is a way of specifiying that the shelled window must be in a
hidden mode (same as opening a form in hidden mode), but I don't comprehend
all the funny stuff in tthe declaration statements etc.

Anyone who can help me with this? The code I'm using:

Option Compare Database
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 ------> may this be a switch ?
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 Declare Function WaitForSingleObject Lib "kernel32" (ByVal _
hHandle As Long, ByVal dwMilliseconds As Long) As Long

Private Declare Function CreateProcessA Lib "kernel32" (ByVal _
lpApplicationName As Long, ByVal lpCommandLine As String, ByVal _
lpProcessAttributes As Long, ByVal lpThreadAttributes As Long, _
ByVal bInheritHandles As Long, ByVal dwCreationFlags As Long, _
ByVal lpEnvironment As Long, ByVal lpCurrentDirectory As Long, _
lpStartupInfo As STARTUPINFO, lpProcessInformation As _
PROCESS_INFORMATION) As Long

Private Declare Function CloseHandle Lib "kernel32" (ByVal _
hObject As Long) As Long

Private Const NORMAL_PRIORITY_CLASS = &H20&
Private Const INFINITE = -1&
Public Sub ExecCmd(cmdline As String)
Dim proc As PROCESS_INFORMATION
Dim start As STARTUPINFO
Dim ReturnValue As Integer

' Initialize the STARTUPINFO structure:
start.cb = Len(start)

' Start the shelled application:
------->I'm sure somewhere here the hidden switch should be specified??
<--------
ReturnValue = CreateProcessA(0&, cmdline$, 0&, 0&, 1&, _
NORMAL_PRIORITY_CLASS, 0&, 0&, start, proc)

' Wait for the shelled application to finish:
Do
ReturnValue = WaitForSingleObject(proc.hProcess, 0)
DoEvents
Loop Until ReturnValue <> 258

ReturnValue = CloseHandle(proc.hProcess)
End Sub

Sub Testing()
ExecCmd "NOTEPAD.EXE"
MsgBox "Process Finished"
End Sub

 

[Douglas J. Steele]

Take a look at http://www.mvps.org/access/api/api0004.htm at "The Access
Web"

wShowWindow takes the same values as the Shell function: vbHide (0),
vbNormalFocus (1), vbMinimizedFocus (2), vbMaximizedFocus(3),
vbNormalNoFocus (4) or vbMinimizedNoFocus (6)