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S.7 Advanced Understanding of Application |
Advanced Understanding of Application Termination
In this advanced discussion, we explore how SheerPower's virtual machine (SPVM) automatically handles system shutdowns, process terminations, and application window closures gracefully. This ensures that applications exit cleanly without requiring developers to manually implement complex shutdown handling.
Understanding Application Termination
When a SheerPower program is running, it operates within the SPVM virtual machine, which automatically handles all system, application, and user-triggered events that lead to application termination. In these cases, SheerPower ensures a graceful cleanup of resources and exits. The termination events include:
- Application Crashing Due to a Programming Bug – If the application encounters an unhandled exception and crashes.
- User Manually Closing the Application Window – When the user clicks the close button.
- User sign out – When a user signs out without first closing the application.
- System Shutdown – When the system system shuts down without first closing the application.
- Process Termination via the TASKKILL Command – If a user
terminates the process using
taskkill /IM - Process Termination Using Windows Task Manager – When
the user selects
End taskfrom theProcessestab in the Task Manager.
Note: Avoid using End Process or End Process Tree from the Task Manager’s Details tab. These options terminate the application immediately without sending shutdown messages, preventing a graceful exit.
Likewise, using taskkill /F forcefully ends the application
without warning, causing the same issue.
Graceful Cleanup of Resources
The virtual machine ensures that the following resources are gracefully handled before termination:
- Application window cleanup – UI resources are freed when the window closes.
- Database tables – Tables are unlocked, flushed, committed, and closed to prevent the loss of any transactions.
- Open files – Files are flushed and closed to prevent data loss.
Conclusion
By automatically handling system shutdowns, forced terminations, and window closures at the virtual machine level, SheerPower ensures graceful exits and automatic cleanup, eliminating the need for developers to worry about writing custom shutdown code.