m12-lifecycle

name	m12-lifecycle
description	Mastering C++ Lifecycle: RAII, Destructors, Static Initialization, Rule of 5.

C++ Resource Lifecycle

Core Question

When does this die?

• Stack: End of scope }.
• Heap: When delete (or smart pointer drop) occurs.
• Static: At program exit (reverse init order).

Error → Design Question

Issue	Design Question
Resource Leak	Did you manually open() without a wrapper class?
Use After Free	Did you capture a reference to a local variable in a lambda/thread?
Static Fiasco	Do statics depend on each other? (Use Meyers Singleton).

Thinking Prompt

1. Does it have a destructor?

   • Yes → RAII. Good.
   • No → Wrap it.

2. Does it copy?

   • FILE* cannot copy. Delete copy constructor.

Quick Reference

Pattern	Use Case
RAII Wrapper	FileHandle, LockGuard.
Scope Guard	std::scope_exit (Cleanup callback).
Rule of 5	Copy/Move/Destructor implementation logic.