138: Pointers

Explain xkcd: It's 'cause you're dumb.
Revision as of 17:08, 3 August 2012 by Xuanji (talk | contribs) (Xuanji moved page 138 to Pointers: Title of comic)
Jump to: navigation, search

Template:ComicHeader

pointers.png

Image Text

Every computer, at the unreachable memory address 0x-1, stores a secret. I found it, and it is that all humans ar-- SEGMENTATION FAULT.

Description

This comic is about a play on the dual meaning of the word “pointer”. Cueball is playing a computer game in the comic, but he seems to be stuck. So he askes Black Hat for a few tips (“pointers”) to get unstuck again. Black Hat wants to be annoying, so he spits out a couple of (seemingly random) 32-bit hexadecimal addresses, which are “pointers” in a programming language. These pointers are used to access a certain location in the computer's memory in order to fulfill a task. Cueball then hates Black Hat for not answering his question.

The "segmentation fault" the image text is referencing also arises from this kind of memory access. If you define a pointer to an invalid address, then try to access the memory location associated with it, you could end up with this exception. The hexadecimal address 0x-1 is one of those invalid access pointers, because memory locations generally start at numeric location 0.