Maybe it's stupid or obvious but I couldn't google any answer. What character ends a null-terminated string in C++11? NULL (which is in fact 0) or new nullptr? On the one hand, nullptr is supposed to replace NULL. On the other, though, I'm not sure if nullptr is a character at all. Or can be interpreted as one.
NULL and nullptr has little to do with null-terminated strings. Both NULL and nullptr are used to denote a pointer which points to nothing, ie. null.
The null-termination of c-style strings is still (and has always) been denoted by a CharT having the integral value 0; or as it's most often written when talking, through a char-literal; '\0'.
Remember that character types are nothing more than integral types with some special meaning.
Comparing a char to an int (which is the type of literal 0) is allowed, it's also allowed to assign the value 0 to a char, as stated: a character type is an integral type.. and integral types hold integral values.
Why this confusion?
Back in the days when we didn't have nullptr, instead we had the macro NULL to denote that a certain pointer didn't have anything to point towards. The value of NULL is, and was, implementation-specific but the behaviour was well-defined; it shall not compare equal to any pointer value that is actually pointing to something.
As a result of how the behaviour of NULL was described plenty of compilers used #define NULL 0, or similar construct, resulting in a "feature" where one could easily compare NULL to any integral type (including char) to see if it's relation to the value zero.
With the previously stated in mind you'd often stumbled upon code such as the below, where the for-condition would be equivalent of having *ptr != 0.
char const * str = "hello world";
for (char const * ptr = str; *ptr != NULL; ++ptr) {
...
}
Lesson learned: Just because something works doesn't mean that it is correct...
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