Exe instance question

[Cor]

I have the following situation.

Start test.exe

Start the same program test.exe for the second time

The first instance must be closed and the second must be opened.

Is there a way to do this?

[freak]

If I remember right, there was a snipped on the Recource Site that does
that. Have a search there, maybe you find it.

You can also have a look at the source of the Editor. It behaves in a
similar way (if a second instance is opened, the second one get's closed)

Timo

[Cor]

Thanks Freak

[Berikco]

Here an small example

Code: Select all

ERROR_ALREADY_EXISTS = 183
Global WM_ACTIVATEOLDINST
WM_ACTIVATEOLDINST = RegisterWindowMessage_("WM_ACTIVATEOLDINST_PB")
MutexName$ = "mylittletestapp"

Procedure MyWindowCallback(WindowID, Message, wParam, lParam)  
  Result = #PB_ProcessPureBasicEvents  
  If message = WM_ACTIVATEOLDINST
    CloseHandle_(hMutex)
    OpenConsole()
    PrintN("closing app")
    Delay(2000)
    End
  EndIf
  ProcedureReturn Result  
EndProcedure  

hMutex = CreateMutex_(0, 0, @MutexName$)
If GetLastError_() = ERROR_ALREADY_EXISTS 
  SendMessage_(#HWND_BROADCAST, WM_ACTIVATEOLDINST, 0, 0)
  Delay(100)
EndIf


If OpenWindow(0,100,150,450,200,#PB_Window_SystemMenu,"MyLittleTestApp " + Str(Random(500)))
  SetWindowCallback(@MyWindowCallback()) 
  Repeat
    ev=WaitWindowEvent()
  Until ev=#PB_EventCloseWindow
EndIf

If hMutex <> 0 
 CloseHandle_(hMutex)
EndIf

End

[PB]

> Here an small example

Here's an even smaller example:

Code: Select all

; These two lines prevent this app from being run more than once.
; You must put these lines at the start of your app's code (obviously).
MutexID=CreateMutex_(0,1,"YourAppName") : MutexError=GetLastError_()
If MutexID=0 Or MutexError<>0 : ReleaseMutex_(MutexID) : CloseHandle_(MutexID) : End : EndIf
;
; Your app's code now goes here, until quitting time, which executes the next line.
;
CloseHandle_(MutexID) : End

[Berikco]

> Here an small example

Here's an even smaller example:

The first instance must be closed and the second must be opened.

No PB, you did not read the whole question, to fast again.
First closed.....second....

[PB]

> No PB, you did not read the whole question, to fast again.
> First closed.....second....

[Thade]

Just for curiosity ...

What situation could make it worth to start the same program twice only to close the first one immediately after you started the second one?
Or did I miss the point somehow?
I mean: what can the same program do at its second start what it cannot do at first try?

[dagcrack]

Hmm Dunno! maybe his proggy is a trial release and each time you open it you have less runs to go ? Just wondering heh..

[Rescator]

Here is a modification of the above code!
It let you do single instance running just like any "good" application!

Run the program, minimize the window. Then run it again!
If all goes well the program won't start again,
but instead message the old instance and restore it and bring it to the foreground!

Only tested on XP Pro, but should behave in a similar way on all windows versions. not entirely sure if W95 behave exactly the same or not, test to be sure!

Code: Select all

ERROR_ALREADY_EXISTS = 183
Global WM_ACTIVATEOLDINST
WM_ACTIVATEOLDINST = RegisterWindowMessage_("WM_ACTIVATEOLDINST_PB")
MutexName$ = "mylittletestapp"

Procedure MyWindowCallback(WindowID, message, wParam, lParam)
 Result = #PB_ProcessPureBasicEvents
 If message = WM_ACTIVATEOLDINST
  ShowWindow_(WindowID,#SW_RESTORE)
  SetForegroundWindow_(WindowID)
  EndIf
 ProcedureReturn Result
EndProcedure

hMutex = CreateMutex_(0, 0, @MutexName$)
If GetLastError_() = ERROR_ALREADY_EXISTS
  SendMessage_(#HWND_BROADCAST, WM_ACTIVATEOLDINST, 0, 0)
  End
EndIf


hwnd=OpenWindow(0,100,150,450,200,#PB_Window_SystemMenu|#PB_Window_MinimizeGadget,"MyLittleTestApp ")
If hwnd
  SetWindowCallback(@MyWindowCallback())
  Repeat
   ev=WaitWindowEvent()
   If showoldwindow
   EndIf
  Until ev=#PB_EventCloseWindow
EndIf

If hMutex <> 0
 CloseHandle_(hMutex)
EndIf

End

I'll leave it up to you as a coding exercise to find out how to send a message to the old (first) app with a filepath. (like many editors do)
Shouldn't be hard, the messaging "example" is already here so. Hehe!

[dibor]

Code: Select all

;--------Prevent app from being run more than once.---------------
*a = CreateSemaphore_(NULL,0,1,GetProgramName())
  If *a < > 0 And GetLastError_()= #ERROR_ALREADY_EXISTS
   CloseHandle_(*a)
   End
 EndIf
;---------------------------------------------------------

[Quin]

Using a mutex works if you simply want to exit the new instance, but what if you want to focus the window of the previous one (e.g. if the user clicks on the desktop icon to restore a minimized application)? I found some code around here somewhere using filemappings, but it's seemingly broken on 6.1x. Does anyone have a method for doing this?
Thanks.

[TassyJim]

Using a mutex works if you simply want to exit the new instance, but what if you want to focus the window of the previous one (e.g. if the user clicks on the desktop icon to restore a minimized application)? I found some code around here somewhere using filemappings, but it's seemingly broken on 6.1x. Does anyone have a method for doing this?
Thanks.

I send the commandline parameters to the running instance using TCPIP before closing the second instance.
Using TCPIP can also be used by other programs to test for a running instance instead of using a mutex

Jim

[Axolotl]

This question has nothing to do with this (very) old thread.
But if you are on windows try this

[RASHAD]

Simple and concise
For Windows

Code: Select all

#MyApp = "Test TEST"

Repeat 
  stx+1
  hwnd = FindWindow_(0,#MyApp)
Until hwnd Or stx > 1000
If hwnd
  SendMessage_(hwnd, #WM_SYSCOMMAND, #SC_CLOSE, 0)
EndIf

flags = #PB_Window_SystemMenu| #PB_Window_MaximizeGadget| #PB_Window_MinimizeGadget| #PB_Window_ScreenCentered | #PB_Window_SizeGadget
OpenWindow(0,0,0,400,300,"Test TEST",Flags)
StringGadget(0,10,10,120,30,"First Window")
Repeat           
  Select WaitWindowEvent()      
      Case #PB_Event_CloseWindow
            Quit = 1 
      Case #PB_Event_Gadget
        Select EventGadget()
          Case 0
            SetGadgetText(0,"Second Test")
        EndSelect
  EndSelect 
Until Quit = 1
End