To synchronously shell an application from a 16-bit VB application, some people write code like this:
Const HINSTANCE_ERROR% = 32Dim hInstChild As Integer'Shell program, if Shell worked, enter loophInstChild = Shell(strExeName, intCmdShow)If hInstChild >= HINSTANCE_ERROR Then While GetModuleUsage(hInstChild) DoEvents WendEnd IfThis code relies on a 16-bit-only API function, GetModuleUsage. Several 32-bit workarounds have been published, but here is the simplest and most reliable solution I’ve seen:
Declare Function OpenProcess Lib "Kernel32" _ (ByVal dwDesiredAccess As Long, _ ByVal bInheritHandle As Long, _ ByVal dwProcessId As Long) As LongDeclare Function WaitForSingleObject Lib "Kernel32" _ (ByVal hHandle As Long, _ ByVal dwMilliseconds As Long) As LongConst SYNCHRONIZE = &H100000Const INFINITE = &HFFFFFFFFPrivate Function SyncShell(ByVal pathname As String, _ windowstyle As Integer) As BooleanDim ProcessID As LongDim ProcessHandle As Long' In VB4, an error occurs if Shell' fails to start the programOn Error GoTo SyncShell_Error' Shell the program, get its handle, ' and wait for it to terminateProcessID = Shell(pathname, windowstyle)ProcessHandle = OpenProcess(SYNCHRONIZE, True, ProcessID)WaitForSingleObject ProcessHandle, INFINITESyncShell = TrueExit FunctionSyncShell_Error: On Error GoTo 0 SyncShell = False Exit FunctionEnd Function
