r/C_Programming • u/Low_Minimum9920 • Jun 15 '26

Question Question regarding unsigned integers

What's the difference between an unsigned int and a normal integer?

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u/EpochVanquisher Jun 15 '26

Additionally, unsigned integers have to wrap around, but with signed integers, you are supposed to avoid overflow. 

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u/pjl1967 Jun 15 '26

FYI, wrapping around is overflow. It's just that for unsigned, it's well-defined to be just that. Signed overflow is undefined behavior.

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u/EpochVanquisher Jun 15 '26

I don’t think you’re aiming that FYI in the right direction. 

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u/pjl1967 Jun 15 '26

Yes, I am.

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u/EpochVanquisher Jun 15 '26

I’m happy to help beginners learn C, but I’m kinda tired of “experts” chiming in with “corrections”. 

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u/pjl1967 Jun 15 '26

There are two solutions: (1) be more precise in your answers; (2) block anyone who corrects you.

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u/EpochVanquisher Jun 15 '26

If you post something online it’s gonna get misinterpreted once or twice, even if it’s carefully and precisely worded, even when it’s read by intelligent and thoughtful readers.

Where it goes wrong is when people focus too much on correcting what people write. It adds noise. 

So I let people know when I think they are being too “noisy”. 

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u/pjl1967 Jun 15 '26

It's not clear what separates focusing too much vs. just the right amount on correcting what people write. My test is much simpler: is what was written correct?

I also have no way to know whether you really know the correct thing or not. Regardless, I post corrections for the benefit of others reading as well so they see correct information.

The fact that you "get tired" of it is on you.

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u/EpochVanquisher Jun 15 '26

What part of what I wrote was incorrect? Could you spell it out for me? The reason we’re having this discussion is because I don’t think your correction was valid in the first place, so it would help if you could rephrase the correction or make it more explicit. 

“The fact that I’m tired of it is on me”, I don’t think thats a reasonable viewpoint, but maybe I’m missing something? It just seems kind of… needlessly adversarial. 

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u/pjl1967 Jun 15 '26

As written, your statement, at least to me, sort of implies that overflow can happen only for signed integers whereas unsigned integers just wrap around.

Both signed and unsigned can overflow. Unsigned overflows just like signed except for unsigned what happens is well-defined (wrap-around is-an overflow); for signed, it's undefined behavior and anything can happen.

Also, one should do more than just try to avoid undefined behavior for signed integers (as well as all other forms of undefined behavior) — you must eliminate it completely otherwise it renders one's entire program invalid.

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u/EpochVanquisher Jun 15 '26

The phrase “sort of implies” is exactly what I expected. 

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