inet_init函数中的sock_register()函数

内核版本：2.6.18

#define AF_INET        2    /* Internet IP Protocol     */
#define PF_INET        AF_INET

static struct net_proto_family inet_family_ops = {
    .family = PF_INET,
    .create = inet_create,
    .owner    = THIS_MODULE,
}

注册PF_INET协议族。

(void)sock_register(&inet_family_ops)

源代码：

int sock_register(struct net_proto_family *ops)
{
    int err;

    if (ops->family >= NPROTO) {
        printk(KERN_CRIT "protocol %d >= NPROTO(%d)\n", ops->family, NPROTO);
        return -ENOBUFS;
    }
    net_family_write_lock();
    err = -EEXIST;
    if (net_families[ops->family] == NULL) {
        net_families[ops->family]=ops;//inet_family_ops挂到net_families全局数组
        err = 0;
    }
    net_family_write_unlock();
    printk(KERN_INFO "NET: Registered protocol family %d\n",
           ops->family);
    return err;
}