Question

In C++ given an array like this:

unsigned char bogus1[] = {
  0x2e, 0x2e, 0x2e, 0x2e
};

Is there a way to introspect bogus1 to find out is is four characters long?

Answer 1

Sure:

#include <iostream>

int main()
{
  unsigned char bogus1[] = {
    0x2e, 0x2e, 0x2e, 0x2e
  };

  std::cout << sizeof(bogus1) << std::endl;

  return 0;
}

emits 4. More generally, sizeof(thearray)/sizeof(thearray[0]) is the number of items in the array. However, this is a compile-time operation and can only be used where the compiler knows about that “number of items” (not, for example, in a function receiving the array as an argument). For more generality, you can use std::vector instead of a bare array.