what is the diff between char str[] and char * str ?

[JMS]

char *ptr   =  "zipy zippy zoo";
char ptr2[] = "blah blah blah";
char ptr3[15] = "zip zip bip";

foo ( char *myptr)
{
    printf( "%s\n", myptr );
}

int main()
{
   char *ptr4 = new[15];
   strcpy( ptr4, "shazam");

    foo(ptr);
    foo(ptr2);
    foo(ptr3)
    foo(ptr4);

   delete []ptr4;
}

fact is any array of anything is just a pointer. The array syntax just allows you the functionality to associate memory with that pointer. Since they're both pointers the syntax for addressing them is interchangable.

typedef struct MYSTRUCT
{
     int  i;
     char c;
     char z[20];
}  MYSTRUCT, *PMYSTRUCT;

int main()
{
      MYSTRUCT     myArray[10];
      PMYSTRUCT   pMyArray = new MYSTRUCT[10];

      myArray->i   = 1;      // set's the first value of the array
      pMyArray->i = 1;      // set's the first value of the pointer memory

      (myArray+2)->i   = 1;      // set's the third item of the array
      (pMyArray+2)->i = 1;      // set's the third item of the pointed to memory

      myArray[2].i   = 3;    // set's the third item of the array
      pMyArray[2].i = 3;    // set's the third item of the pointed to memory

      delete []pMyArray;
}

base[] == *base derefference
base[#] == *(base+offset) add an offset to the base and dereffrence





arrays are just pointers with memory already associated with them. Pointers are just arrays which may or may not have the memory associated with them.

The only difference I know of is one which SuperKoko touched upon..

You can't change the base address of an array. Pointers you can..

char szbuffer[10] = "";
char *pszBuffer = new char[10];

szBuffer += 1; // ilegal
pszBuffer += 1; // legal


An array contains an address, and a pointer contains an address.
The rest is just syntax.