You forget to call CloseHandle - will there be a memory leak?

Windows programming Interview Questions and Answers

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14. You forget to call CloseHandle - will there be a memory leak?

Well, yes and no. It is possible for a process to leak resources (such as kernel objects) while the process runs. However, when the process terminates, the operating system ensures that any and all resources used by the process are freed—this is guaranteed. For kernel objects, the system performs the following actions: When your process terminates, the system automatically scans the process’s handle table. If the table has any valid entries (objects that you didn’t close before terminating), the system closes these object handles for you. If the usage count of any of these objects goes to zero, the kernel destroys the object.

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Other Interview Questions

• What are types of kernel objects?
• What is a kernel object?
• User can access these kernel objects structures?
• If we cannot alter these Kernel Object structures directly, how do our applications manipulate these kernel objects?
• How owns the Kernel Object?
• How does the kernel object outlive the process that created it?
• Which is the data member common to all the kernel object and what is the use of it?
• How to identify the difference between the kernel object and user object?
• What is the purpose of Process Handle Table?
• Name few functions that create Kernel Objects?
• What is handle?
• How the handle helps in manipulating the kernel objects?
• What happens when the CloseHandle(handle) is called?
• You forget to call CloseHandle - will there be a memory leak?
• What is the need of process relative handles?
• How the handles are handled in the child process?
• Why the entries in the parent process table and child table are same?
• What about the usage count in the parent child process tables?
• What are Named Objects?
• What do you mean by unnamed object?
• What is DuplicateHandle (API)?
• What is a thread?
• What is the limit on per process for creating a thread?
• What is Synchronization Objects?
• What is Event Object and why it is used?
• What is signaled and non signaled state?
• APIs for creating event and set and reset the events
• What is Mutex Object and why it is used?
• How do I create a Mutex?
• How do other threads own the mutex?
• How do other threads own the mutex?