Is std::string always null-terminated in C++11? [duplicate]

Yes, per [string.accessors] p1, std::basic_string::c_str():

Returns: A pointer p such that p + i == &operator[](i) for each i in [0,size()].

Complexity: constant time.

Requires: The program shall not alter any of the values stored in the character array.

This means that given a string s, the pointer returned by s.c_str() must be the same as the address of the initial character in the string (&s[0]).