What are the problems of a zero-terminated string that length-prefixed strings overcome?

Question

What are the problems of a zero-terminated string that length-prefixed strings overcome?

I was reading the book Write Great Code vol. 1 and I had that question in mind.<

Answer 1

First a clarification: C++ strings (i.e. std::string) aren't weren't required to end with zero until C++11. They always provided access to a zero-terminated C string though.

C-style strings end with a 0 character for historical reasons.

The problems you're referring to are mainly bound to security issues: zero ended strings need to have a zero terminator. If they lack it (for whatever reason), the string's length becomes unreliable and they can lead to buffer overrun problems (which a malicious attacker can exploit by writing arbitrary data in places where it shouldn't be.. DEP helps in mitigating these issues but it's off-topic here).