Comment by mpweiher | Hacker News Reader

Comment by mpweiher | Hacker News Reader

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> not null-checking properly,

Fortunately, the run-time does this for you: it ignores messages to nil.

And the framework provides container objects for "bags of bytes": NSData.

So it is actually surprisingly hard to dereference a null pointer, and surprisingly easy to avoid mechanically without being perfect.

Just make sure that you delegate any manipulation of raw data to methods of the object holding the data.

https://blog.metaobject.com/2014/05/the-spidy-subset-or-avoi...

While it is certainly possible to circumvent this if you put your mind to it, it is remarkably safe in practice.

Partially true, because ignoring messages to nil only works with Objective-C data types, any classical C style programming will segfault as in plain C.

Just like in C++, while there are high level abstractions that avoid traditional C memory corruption issues, there are always those that insist in sticking to the C subset.

> any classical C style programming will segfault as in plain C.

As I wrote, you wrap those in an Objective-C container that manages that pointer, and delegate the C access to that container.

So not:

    c_pointer = [container getPointer]
    <munge on pointer>

But rather:

    [container doSomeMungingOnYourCData];

Which is, of course, how you should be doing things in OO style anyhow. So that works out just fine.

But yes, some people do insist on doing things the hard, slow, nasty way. They get punished.

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