Question

I have the following struct in C.

struct a {
    long state;
    long uid;
    long w, x, y, z, xx, yy, zz, xxx, yyy, zzz;
    char comm[64];
};

Then I do a malloc as follows.

buf = malloc (100 * sizeof(struct a));

But when I try to access the individual structs as follows, I get a seg fault.

for (i = 0; i < 100; ++i) {
    tmp = buf + (i * sizeof(struct a));
    printf ("\t>%d>%ld,%ld\n", i, tmp->state, tmp->uid);
}

I am getting a seg fault after the first 10 entries. I have no idea why this happens. Please help.

Answer 1

if buf is a pointer to a struct a, the pointer math should be:

tmp = buf + i;