How
do I tell when an application executed using the SHELL command
is finished?
It is often necessary for a program to know when a shelled application has finished.
We have procedure that does not return control to the rest of the program until the
application that has been shelled is quit. To use this procedure, simply call
ExecCmd(strProgram).
Declarations
This code must be placed in the declarations section of the project. 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
Declare Function WaitForSingleObject Lib _
"kernel32" (ByVal hHandle As Long, ByVal dwMilliseconds _
As Long) As Long
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 Declare
Function CloseHandle Lib "kernel32" (ByVal hObject _
As Long) As Long
Private Const NORMAL_PRIORITY_CLASS = &H20&
Private Const INFINITE = -1&
Prodedure
This is the
code that can be called to execute an external program.
Simply copy this code into the code of your project. To
run an external program, call ExecCmd(program) from anywhere
in your code.
Public Sub ExecCmd(cmdline$)
Dim proc As PROCESS_INFORMATION
Dim start As STARTUPINFO
' Initialize the STARTUPINFO structure:
start.cb = Len(start)
' Start the shelled application:
ret& = CreateProcessA(0&, cmdline$, 0&, 0&, 1&, _
NORMAL_PRIORITY_CLASS, 0&, 0&, start, proc)
' Wait for the shelled application to finish:
ret& = WaitForSingleObject(proc.hProcess, INFINITE)
ret& = CloseHandle(proc.hProcess)
End
Sub
|