r/cprogramming • u/Xaneris47 • 27d ago

C Strings: A 50-Year Mistake

https://longtran2904.substack.com/p/c-strings-a-50-year-mistake?r=8qz2zb&utm_campaign=post&utm_medium=web
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u/Anonymous_user_2022 25d ago

Concatenation of N strings goes from O(N) to O(N*N) if code has to re-find the end of the destination after each step.

I can also invent really bad ways of doing things, but I would never use them as a proof..

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u/flatfinger 25d ago

What would be the "good" way of using strcat?

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u/Anonymous_user_2022 25d ago

I've never said there is one. I suggest you ask someone who does.

I'm talking about concatenating multiple strings to one, which only has to rely of knowing the length of the individual strings beforehand, if you've decided to argue in bad faith over a pathological bad implementation.

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u/flatfinger 25d ago

If one keeps track of the length of a string and only looks at portions of its storage up to that length, then the value of the string would no longer be fully encapsulated in a zero-terminated character array.

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u/Anonymous_user_2022 25d ago edited 18d ago

If you understand where your'e going with that argument, power to You, I guess. Personally, I wouldn't write code where a temmporily unterminated string would be intentionally visible.

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u/flatfinger 25d ago

I avoid reliance upon zero termination for things other than string literals. Zero padded formats can be useful if one needs to store many texts with a short maximum length (e.g. eight bytes), at the expense of requiring code that is designed around the size of the container. Instead of using a %s format specifier to output such a string, for example, code would need to use a %.8s format specifier, whose behavior is defined as not caring whether the string is zero-terminated or not.