unsigned char *__p;
__cmsg_nxthdr (struct msghdr *__mhdr, struct cmsghdr *__cmsg){  unsigned char *__p;  if ((size_t) __cmsg->cmsg_len < sizeof (struct cmsghdr))    /* The kernel header does this so there may be a reason.  */    return NULL;  __p = (((unsigned char *) __cmsg)	 + ((__cmsg->cmsg_len + sizeof (long int) - 1) & ~sizeof (long int)));  if (__p >= (unsigned char *) __mhdr->msg_control + __mhdr->msg_controllen)    /* No more entries.  */    return NULL;  return (struct cmsghdr *) __p;}