🚀 go-pugleaf

On Mon, 18 Jan 1999 01:26:57 -0500, Martin Ambuhl
<mambuhl@earthlink.net> wrote:

> CalvinKong wrote:
> > 
> > I had find out the part that causing the problem . But I still don't know
> > why it occurs .. Logically , it should be okay . Here is a program that I
> > extracted out and modified , please discuss with me ...
> > ************************************************************
> > # include <stdlib.h>
> > typedef struct ListType {
> >  int       item;
> >  struct ListType *link;
> > }Node;
> > typedef Node *List;
> > 
> > int main()
> > {
> >  List temp;
> > 
> >  temp = (List)malloc (sizeof(List));
> 
> sizeof(List) is just the size of a pointer.
> If you would do with a typedef less, you would not confuse yourself:
>    Node *temp;
>    temp = malloc(sizeof *temp);
> /* or, to be slightly less safe, 'temp = malloc(sizeof(Node));' */
> remember to check the return value from malloc.

<Jack>

Martin is absolutely correct, but to be slightly MORE safe:

temp = malloc(sizeof(*temp));

</Jack>
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