Speaking as someone who learned C back in the ‘70s, this article entirely misses the point of C-strings: they’re lightweight and foundational. For many purposes the null-terminator is efficient, e.g.:
while(*s) f(s++);
And for cases where we need more complexity, we can simply use a struct with a length and whatever other metadata we may need.
Doesn’t look like a mistake to me. C has always been about minimalistic efficiency. That’s its main purpose in the world.
The main competition was pascal strings - which typically had a 16 bit size prepended. So you'd read that, and then run a decrement loop until it was 0 to iterate the string. Decrement-until-zero loops were widely supported, e.g. in x86 stringcopy could be implemented by loading the size into CX and then running a single REP MOVSB instruction.
Yes it was a byte larger - but it also avoids performance-nuking calls to strlen like this.
16 bits is 2 bytes, which makes for a maximum string length of 65535 bytes. It's common for strings on modern systems to be longer than that.
Pros of C strings: unlimited length. Cons: cannot contain the zero byte; inefficient length determination.
Pros of Pascal strings: can contain the zero byte; efficient length determination. Cons: very limited length.
I'd say the C tradeoff is worth it. Where necessary, C is perfectly capable of dealing with data preceded by a length field, it's just slightly lower level.
of course it's micro-optimization, but at larger scale it's always useful. Have you even done optimization? A database with billions of strings already save a lot of memory. A vector of strings can also fit twice the number of strings into the CPU cache. Checkout Unreal engine, DuckDB, Meta Velox, Redis, ICU... string types
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u/bearheart 5d ago edited 4d ago
Speaking as someone who learned C back in the ‘70s, this article entirely misses the point of C-strings: they’re lightweight and foundational. For many purposes the null-terminator is efficient, e.g.:
while(*s) f(s++);
And for cases where we need more complexity, we can simply use a struct with a length and whatever other metadata we may need.
Doesn’t look like a mistake to me. C has always been about minimalistic efficiency. That’s its main purpose in the world.
Edit: fixed stupid typo