how much to malloc for struct stat *

The following seg faults eventually

Code:

---

#include <sys/stat.h>
struct stat *fmt;

fmt=malloc(sizeof(struct stat *));
do{
  if(0!=stat(file,fmt)){
    printf("cannot watch the time stamp for the journal file\n");
    exit(1);
    }
  if(wait<MAX_WAIT) wait++;
  epoch=fmt->st_mtime;
  } while(old_epoch>epoch);
free(fmt);

---

If I replace the malloc line with

Code:

---

fmt=malloc(100+sizeof(struct stat *));

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seg faults goes away.

What is the correct way to do this?

Thanks

No need for malloc.

Code:

---

struct stat fmt;
if (0 != stat(file, &fmt))
{
  /* Handle error */
}
else
  epoch = fmt.st_mtime;

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That's much better. Thanks.

If you really did want to use malloc, it should be:

Code:

---

fmt = malloc(sizeof(struct stat));

---

or better yet:

Code:

---

fmt = malloc(sizeof(*fmt));

---