Pointer vs Array in C
Most of the time, pointer and array accesses can be treated as acting the same, the major exceptions being:
1. the sizeof operator
- sizeof(array) returns the amount of memory used by all elements in the array
- sizeof(pointer) only returns the amount of memory used by the pointer variable itself
2. the & operator
- array is an alias for &array[0] and returns the address of the first element in the array
- &pointer returns the address of the pointer
3. a string literal initialization of a character array
- char array[] = âabcâ sets the first four elements in array to âaâ, âbâ, âcâ, and â\0â
- char *pointer = âabcâ sets the pointer to the address of the âabcâ string (which may be stored in read-only memory and thus unchangeable)
4. Pointer variable can be assigned a value whereas an array variable cannot be.
int a[10]; int *p; p=a; /*legal*/ a=p; /*illegal*/
5. Arithmetic on pointer variable is allowed.
p++; /*Legal*/ a++; /*illegal*/
6. Array is a collection of similar data types while the pointer variable stores the address of another variable.
Please refer Difference between pointer and array for more details.