How can I append part of an array of characters to a string?

Question

Suppose I have a std::string object and a null-terminated array of characters (or C-style string):

std::string str("This is a ");

const char* cstr = "strings are a really important data type.";

How can I append just the first N characters (in this case, 6, so that str will contain This is a string) of a C-style string to a std::string in the cleanest and most efficient way possible?

Answer 1

How about the append method?

str.append(cstr, 6);