Programming

Hi Shamrock,

*ptr has already been initialized with address of local variable 'array' as -

*ptr = &array; in statement int **ptr = &array;

ptr(int**) -> array(int*) -> (uninitialized/invalid reference to integer).

ptr = &array;

*ptr (or array) = (int*)calloc(n,sizeof(int)); will initialize array to hold address of allocated memory.

Correction -

*ptr has already been initialized with address of local variable 'array' as -
*ptr = &array; in statement int **ptr = &array;

ptr has already been initialized with address of local variable 'array' as -
ptr = &array; in statement int **ptr = &array;

Sorry Shamrock but I did not understand your answer.Should ptr be a pointer to array??
I tried the following and it seems to work fine:

int main(){
int *array;
int **ptr = &array;
sub(ptr);
}
void sub(int **ptr){
//calculates n...
int *tmp=(int*)calloc(n,sizeof(int));
for(i=0;i<n;i++)
tmp[i]=i;
*ptr=tmp;
}

littleboyblu,

Can you try this one -

void main(){
int *array;
int **ptr = &array;
sub(ptr);
}

void sub(int **ptr){
....//calculates the array dimension
*ptr = calloc(n,sizeof(int));
for(i=0;i<n;i++)
(*ptr)[i]=i; // subscript operator [] have higher precedence than dereference * operator
}

thanks pshaikh