Thread: malloc/realloc

Everytime i think i get this i mess it up.

Code:

#include<stdio.h>
#include<math.h>
typedef int boolean;
#define true 1
#define false 0
char Shift(char Achar,int Shifts)
{
    boolean Shiftleft =
    Shifts <= 0;
    if (Shiftleft)
     Shifts=sqrt(pow(Shifts,2)); //i wonder if -1*val would be faster
    int Lowerbound = 33;
    int Remainder;
    int Upperbound = 126;
    Remainder =
Shifts%(Upperbound-Lowerbound);
    if (Shiftleft)
    {
        if (Remainder>
        (int)Achar-Lowerbound)
        {
            return (char)(Upperbound+(((int)Achar-Lowerbound)-Remainder)+1);
        }
        else return (char)((int)Achar-Remainder);

    }
    else
    {
        if (Remainder>
        Upperbound-(int)Achar)
         {
            return (char)(Lowerbound+(Remainder-(Upperbound-(int)Achar))-1);
        }
        else return (char)((int)Achar+Remainder);
    }
}
int Encryption(char *AString,char *Buffer,int *NewLength)
{
int i = 0 ;
*NewLength = strlen(AString)+1;
Buffer = malloc(*NewLength);
printf("Func Length : %i\n",*NewLength);
for (i;i!=*NewLength;i++)
{
 Buffer[i]=AString[i];
}
Buffer[i+1]='\0';
printf("In Func: %s\n",Buffer);
return 1;
}

#include<stdio.h>
#include<stdlib.h>

int Changec(char *Arr)
{
    Arr[1]='G';
    return 1;
}
void Changei(int *Pointer)
{
    *Pointer=3;
}


int main(void)
{
    int strLength;
    char NewStr[0];
    Encryption("a",NewStr,&strLength);
    printf("Encrypted Str : %s\n",NewStr);
    printf("New Length : %i\n",strLength);

    return 0;
}

The encrypted string comes back as a smiley face. A very...very...friendly smiley.
Any Help?

If someone could explain how to use malloc and realloc properly that'd be nice XC