VB aplication external process hangs

[skynetosiris]

im using the attached process to run an external program, everything works fine, but whenever the external program hangs my application hangs, how can i implement a timer to stop the application if the external program hangs?

thanks in advance

Public Function ExecuteApp(sCmdline As String) As String
Dim proc As PROCESS_INFORMATION, ret As Long
Dim start As STARTUPINFO
Dim sa As SECURITY_ATTRIBUTES
Dim hReadPipe As Long 'Este Handle lee el Pipe.
Dim hWritePipe As Long 'A este pipe se redirecciona StdOutput y StdErr.
Dim sOutput As String
Dim lngBytesRead As Long, sBuffer As String * 256

sa.nLength = Len(sa)
sa.bInheritHandle = True

ret = CreatePipe(hReadPipe, hWritePipe, sa, 0)
If ret = 0 Then
MsgBox "CreatePipe failed. Error: " & Err.LastDllError
Exit Function
End If

start.cb = Len(start)
start.dwFlags = STARTF_USESTDHANDLES Or STARTF_USESHOWWINDOW
' Redirecciona la salida estandar y los errores al mismo pipe
start.hStdOutput = hWritePipe
start.hStdError = hWritePipe
start.wShowWindow = SW_HIDE

ret = CreateProcessA(0&, sCmdline, sa, sa, True, NORMAL_PRIORITY_CLASS, 0&, 0&, start, proc)
If ret = 0 Then
MsgBox "CreateProcess failed. Error: " & Err.LastDllError
Exit Function
End If

CloseHandle hWritePipe

' Lee el texto del shell
' hasta 256 caracteres a la vez
Do
ret = ReadFile(hReadPipe, sBuffer, 256, lngBytesRead, 0&)
sOutput = sOutput & Left$(sBuffer, lngBytesRead)
Loop While ret <> 0 ' if ret = 0 ya no hay caracteres que leer

CloseHandle proc.hProcess
CloseHandle proc.hThread
CloseHandle hReadPipe

ExecuteApp = sOutput ' Regresa el resultado.
End Function