Pointers

The address of a variable

1. address.C: output the address of a variable in hexadecimal.

   The value of i is 10
   The address of i is 0x7fff2757276c
   The number of bytes in i is 4
   

2. Store the address of a variable into a pointer.
   Diagram with pointer pointing left.
   1. pointerint.C: store the address of an int into a “pointer to an int”.
   2. pointerdouble.C: store the address of a double into a “pointer to a double”.
3. Use the unary * operator to dereference the pointer, i.e., get the value to which the pointer points.
   (The binary * operator means multiplication.)
   1. dereferenceint.C
   2. dereferencedouble.C
4. neighbor.C. A pointer also gives us access to the values that are neighbors of the pointed-to value.
5. struct.C: use the unary * operator to dereference a “pointer to a structure” to get the value of each field of the original structure.