How to append char data to a std::vector without causing a copy

Question

I have a vector of chars which contains some data elements.

std::vector<unsigned char> data_1;

I have an unsigned char * which is pointing another set of data elements.

unsigned char * data_2;

Question:
Is there a way I can merge data_2 into data_1 which is a vector without causing a copy of the data elements at all?

I read about move semantics being referred in this discussion but I am a bit unsure if it is possible in this situation I have here.

Answer 1

Is there a way I can merge data_2 into data_1 which is a vector without causing a copy of the data elements at all?

No. All ways of inserting elements into a vector require copying (or moving) each element at least once.

I read about move semantics being referred in this discussion but I am a bit unsure if it is possible in this situation I have here.

Moving a char is same as copying a char. The distinction is only relevant to class types with a non-trivial move constructor or move assignment operator.

It wouldn't be possible even if data_2 was a std::vector<unsigned char>?

Appending without copying (or moving) would not be possible even then.

Sidenote 1: You can replace the entire content of one vector with content of another vector without copying (or moving) any elements by using move assignment operator of the vector.

Sidenote 2: You can merge two instances of node based containers such as std::lists, std::sets, std::maps and their unordered counterparts without copying (nor moving) any of the elements.