Detect if a certain application is running?

[Legacy 98055]

Wrong forum? So what. I have had good luck here with questions such as these.

If I have App_A running and want to prevent the user from running another instance of the same app, how might I detect if this App is running? The application contains no windows.

Thanks,
Tom

 

[Colo]

How about use Mutex of API? When you run the App, create "Test Mutex", and when quit the App, use ReleaseMutex function.

here is a sample...<PRE>Private Declare<FONT color=red>Function</FONT>CreateMutex Lib "kernel32" Alias "CreateMutexA" ( _<FONT color=red>ByRef</FONT> lpMutexAttributes<FONT color=red>As</FONT> Any, _<FONT color=red>ByVal</FONT> bInitialOwner<FONT color=red>As</FONT><FONT color=red> Long</FONT>, _<FONT color=red>ByVal</FONT> lpName<FONT color=red>As</FONT><FONT color=red> String</FONT>)<FONT color=red>As</FONT><FONT color=red> Long</FONT>

Private Declare<FONT color=red>Function</FONT>ReleaseMutex Lib "kernel32" ( _<FONT color=red>ByVal</FONT> hMutex<FONT color=red>As</FONT><FONT color=red> Long</FONT>)<FONT color=red>As</FONT><FONT color=red> Long</FONT>

Private Declare<FONT color=red>Function</FONT>OpenMutex Lib "kernel32" Alias "OpenMutexA" ( _<FONT color=red>ByVal</FONT> dwDesiredAccess<FONT color=red>As</FONT><FONT color=red> Long</FONT>, _<FONT color=red>ByVal</FONT> bInheritHandle<FONT color=red>As</FONT><FONT color=red> Long</FONT>, _<FONT color=red>ByVal</FONT> lpName<FONT color=red>As</FONT><FONT color=red> String</FONT>)<FONT color=red>As</FONT><FONT color=red> Long</FONT>

Private Declare<FONT color=red>Function</FONT>CloseHandle Lib "kernel32" ( _<FONT color=red>ByVal</FONT> hObject<FONT color=red>As</FONT><FONT color=red> Long</FONT>)<FONT color=red>As</FONT><FONT color=red> Long</FONT>



Private<FONT color=red>Const</FONT>ERROR_ALREADY_EXISTS = 183&

Private<FONT color=red>Const</FONT>MUTEX_ALL_ACCESS = &H1F0001

Private lngMutex<FONT color=red>As</FONT><FONT color=red> Long</FONT><FONT color=red>Sub</FONT>Autpen()

lngMutex = OpenMutex(MUTEX_ALL_ACCESS, 0, "Test Mutex")<FONT color=red>If</FONT>lngMutex = 0 Then

lngMutex = CreateMutex(<FONT color=red>ByVal</FONT> 0, 0, "Test Mutex")<FONT color=red>Else</FONT><FONT color=red>Call</FONT> CloseHandle(lngMutex)<FONT color=red>Call</FONT> MsgBox("The App is running already")<FONT color=red>End If</FONT><FONT color=red>End Sub</FONT><FONT color=red>Sub</FONT>Auto_Close()<FONT color=red>Call</FONT> ReleaseMutex(lngMutex)<FONT color=red>End Sub</FONT></PRE>

_________________
With Regards,
Colo

You can release your free soft ware on my site. Please email your file to me. Thanks.
This message was edited by Colo on 2002-08-25 23:14

 

[Legacy 98055]

Hi Colo.
Your time was not wasted. I will save your example when using Excel. This was for a VB app and I should have specified that.

If App.PrevInstance = True Then
MsgBox "This program is already running."
End
End If

Thanks,
Tom

 

[Ivan F Moala]

On 2002-08-25 21:11, TsTom wrote:
Wrong forum? So what. I have had good luck here with questions such as these.

If I have App_A running and want to prevent the user from running another instance of the same app, how might I detect if this App is running? The application contains no windows.

Thanks,
Tom

Hi Tom
Try this ?? Note your'll need the Applications Class Name.

<pre/>
Function IsAppARunning() As Boolean
// Returns False if NOT running
Dim objApp As Object

Const ERR_APP_NOTRUNNING As Long = 429
On Error Resume Next

Set objApp = GetObject(, "ClassName")

If Err <> ERR_APP_NOTRUNNING Then
MsgBox "You must close AppA if you want to run this program" _
& vbCrLf & "Close AppA and try again", , "Warning"
IsAppARunning = True
Exit Function
Else
IsAppARunning = False
End If

End Function

</pre>

 

[Colo]

On 2002-08-25 23:15, TsTom wrote:
Hi Colo.
Your time was not wasted. I will save your example when using Excel. This was for a VB app and I should have specified that.

If App.PrevInstance = True Then
MsgBox "This program is already running."
End
End If

Thanks,
Tom

Thanks Tom,
I wanted to say is... When you run Another App from your code, Create Mutex.
But Ivan's way is better...for all I know.