Specifies a function to run automatically when the script exits.

OnExit Func , AddRemove



A function name or function object to call when the script is exiting. The function can optionally define parameters as shown below. If an OnExit function returns a non-zero integer, the script does not exit. Otherwise, the script exits after all registered functions are called.

MyFunction(ExitReason, ExitCode)

One of the following values:
1 (the default): Call the function after any previously registered functions.
-1: Call the function before any previously registered functions.
0: Do not call the function.


Any number of OnExit functions can be registered. An OnExit function usually should not call ExitApp; if it does, the script terminates immediately.

OnExit functions are called when the script exits by any means (except when it is killed by something like "End Task"). It is also called whenever #SingleInstance and Reload ask a previous instance to terminate.

A script can detect and optionally abort a system shutdown or logoff via OnMessage(0x11, "WM_QUERYENDSESSION").

The OnExit thread does not obey #MaxThreads (it will always launch when needed). In addition, while it is running, it cannot be interrupted by any thread, including hotkeys, custom menu items, and timed subroutines. However, it will be interrupted (and the script will terminate) if the user chooses Exit from the tray menu or main menu, or the script is asked to terminate as a result of Reload or #SingleInstance. Because of this, an OnExit function should be designed to finish quickly unless the user is aware of what it is doing.

If the OnExit thread encounters a failure condition such as a runtime error, the script will terminate.

If the OnExit thread was launched due to an Exit or ExitApp function that specified an exit code, that exit code is used unless an OnExit function returns true (preventing exit) or calls ExitApp.

Whenever an exit attempt is made, each OnExit function starts off fresh with the default values for settings such as SendMode. These defaults can be changed in the auto-execute section.

If an OnExit function declares parameters, its first parameter is one of the following words:

Logoff The user is logging off.
Shutdown The system is being shut down or restarted, such as by the Shutdown function.
Close The script was sent a WM_CLOSE or WM_QUIT message, had a critical error, or is being closed in some other way. Although all of these are unusual, WM_CLOSE might be caused by WinClose having been used on the script's main window. To prevent this, dismiss the main window with Send "!{F4}".
Error A runtime error occurred in a script that is not persistent. An example of a runtime error is Run/RunWait being unable to launch the specified program or document.
Menu The user selected Exit from the main window's menu or from the standard tray menu.
Exit The Exit or ExitApp function was used (includes custom menu items).
Reload The script is being reloaded via the Reload function or menu item.
Single The script is being replaced by a new instance of itself as a result of #SingleInstance.


OnMessage, RegisterCallback, OnClipboardChange, ExitApp, Shutdown, #Persistent, Threads, Gosub, Return


The following example uses #Persistent to prevent the script from exiting automatically. After running the script, right click the tray icon and click Exit to test the OnExit function. Then click "Yes" to terminate the script or "No" to keep it running.


; Register a function to be called on exit:

; Register an object to be called on exit:
OnExit(ObjBindMethod(MyObject, "Exiting"))

ExitFunc(ExitReason, ExitCode)
    if ExitReason != "Logoff" and ExitReason != "Shutdown"
        Result := MsgBox("Are you sure you want to exit?",, 4)
        if Result = "No"
            return 1  ; OnExit functions must return non-zero to prevent exit.
    ; Do not call ExitApp -- that would prevent other OnExit functions from being called.

class MyObject
        MsgBox "MyObject is cleaning up prior to exiting..."