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iOS Objective-C Basics (Retired) Pointers and Memory Pointers

Posted by Jake Nisenboim
Jake Nisenboim
3,374 Points

Understanding addresses and pointers [in C]

My understanding is that pointers are specific to saving memory?

They follow variables without having to hold the large amounts of data. I can later call the variable x by pointing to it rather than copying it.

How does that save memory?

Addresses are the places in memory in which the objects or variables are located.

Is this correct?

Thank you.

1 Answer

Martin Wildfeuer
PLUS
Martin Wildfeuer
Courses Plus Student 11,071 Points
Martin Wildfeuer
Martin Wildfeuer
Courses Plus Student 11,071 Points

My understanding is that pointers are specific to saving memory?

Originally, yes. There's a bit more to it, though, have a look at Why C Pointers by Andrew Hardwick, that's a good read.

How does that save memory?

A pointer is a reference (the address) to data in memory. This data could be an instance of a person class, for example. This person object takes, let's say 50 kB of memory. By passing around this data via pointers, it will only ever take this 50 kB of memory. If it was copied, however, it would use another 50 kB of memory with every copy.

I hope this makes any sense, I always find myself in trouble when trying to find the right words for explaining pointers ;)