Thread: doesnt return allocated memory

hello i m supposed to make a program that should allocate according to va_start then allocate according to num of parameter specified by first parameter i did everything according but i only got first 2 members of the arguments

Code:

#include <stdio.h>
#include <stdarg.h>
#include <stdlib.h>
#define ParseSize(x) (x) + (sizeof x/sizeof x[0])
int * new_i_arrays(int lim,...)
{

    va_list ap;                   // declare object to hold arguments

    int *arr;

    int i;

    va_start(ap, lim);            // initialize ap to argument list
    arr=(int*)calloc(lim,sizeof(int));

    for (i = 0; i < lim; i++)

       arr[i] = va_arg(ap, int); // access each item in argument list

    va_end(ap);                   // clean up

    return arr;

}


void ShowArr(int *arr,int *Size) {
    while( arr < Size )
        printf("%d\n",*arr++);
    putchar('\n');
}
int main(void)
{
    int *p1;
    int *p2;
    p1=new_i_arrays(5,1,2,3,5,7);
    p2=new_i_arrays(3,1,2,3);
    ShowArr(p1,ParseSize(p1));
    ShowArr(p2,ParseSize(p2));
    free(p1);//free allocated memory
    free(p2);//free alocated memory
    return 0;
}

>> #define ParseSize(x) (x) + (sizeof x/sizeof x[0])

That only works for stack-declared arrays, and even then only if referred to directly by name (eg: you couldn't form a pointer to it and then pass it to the macro, nor could you pass it to a function and obtain the correct calculation). Sorry, that's just how C works - you'll need to store the size somewhere.

>> void ShowArr(int *arr,int *Size) {

Really bad choice of a variable name there. I would think it was a pointer to a variable containing the size information, considering it's name. Maybe something like "arr_end" would be more appropriate.

yes i totally forgot i declared it in the heap
but shouldnt it work since i already allocated it on the heap ? then it will be like a array since i alrdy allocated it ?

Code:

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

int * new_i_arrays(int lim,...) {

    va_list ap;                   // declare object to hold arguments
    int *arr;
    int i;

    va_start(ap, lim);            // initialize ap to argument list

    arr=(int*)calloc(lim,sizeof(int));
    for (i = 0; i < lim; i++)
       arr[i] = va_arg(ap, int); // access each item in argument list

    va_end(ap);                   // clean up
    return arr;

}


void ShowArr(int *arr,int arr_end) {
    int i=0;
    while( i < arr_end )
        printf("%d\n",arr[i++]);
    putchar('\n');
}
int main(void)
{
    int *p1;
    int *p2;
    p1=new_i_arrays(5,1,2,3,5,7);
    p2=new_i_arrays(3,1,2,3);
    ShowArr(p1,5);
    ShowArr(p2,3);
    free(p1);//free allocated memory
    free(p2);//free alocated memory
    return 0;
}

as for var names i not that great in doing names :P