Hey! The author wrote PuTTY!
That was a very informative read. I feel like I am the exact target audience: I'm coming from a programing background steeped in C# and I'm learning C from the K&R book.
That was a very informative read. I feel like I am the exact target audience: I'm coming from a programing background steeped in C# and I'm learning C from the K&R book.
https://modernc.gforge.inria.fr
The page has a link to a free PDF version.
I believe once upon a time Rust needed a lot more hand-holding rather than just inferring lifetimes from scope, but in modern Rust the behaviour feels pretty natural for scopes.
Scope is the region of program text in which an identifier is visible.
Lifetime is the duration during program execution in which an object (stored in memory) exists.
If you define a local variable, the scope of its identifier extends from its declaration to the end of the enclosing block; its lifetime is the execution of the enclosing block.
If you allocate an object on the heap by calling `malloc()`, its lifetime ends when its deallocated by calling `free()`.
An object defined at file scope or with the `static` keyword has a lifetime that's the entire execution of the program.
In either case, if you have a pointer to the object, that pointer becomes invalid when the object it points to reaches the end of its lifetime. (And C doesn't make it particularly difficult to cause problems by trying to access an object that no longer exists.)