Assign char array to another char array

Question

I know we can not assign a char array to another char array like:

 char array1[] = "Hello";
 char array2[] = "Hi!";

 array1 = array2;//does not compile

But:

 char array1[] = "Hello";
 char *array2 = NULL;

 array2 = array1; //compile

 printf("%s", array2); //display Hello

This works.

Can anyone please explain why?

Thanks!

Answer 1

Plain arrays are not assignable. That is why the first code sample doesn't work.

In the second sample, array2 is just a pointer, and array1, despite being an array, can decay to a pointer to its first element in certain situations. This is what happens here:

array2 = array1;

After this assignment, the pointer array2 points to the first element of the array array1. There has been no array assignment, but, rather, pointer assignment.