LinuxQuestions.org - sendto function does not use MAC address provided in struct sockaddr

I am trying to send an OAM ethernet frame using raw socket. I was successful in doing so.

The send function I have written is:

Code:

int send_frame(sock_info *info,char *buf,int length)

        {

              struct sockaddr_ll dest_addr;

              memset(&dest_addr,0,sizeof(struct sockaddr_ll));

              dest_addr.sll_family = PF_PACKET;

              dest_addr.sll_protocol = htons(8902);

              dest_addr.sll_ifindex = info->if_index;

              dest_addr.sll_halen = ETH_MAC_ADDR_LEN;

              dest_addr.sll_pkttype = PACKET_OTHERHOST;

              dest_addr.sll_hatype  = ARPHRD_ETHER;

              memset(dest_addr.sll_addr,0,8);

        

              dest_addr.sll_addr[0] = 0x00;

              dest_addr.sll_addr[1] = 0xE0;

              dest_addr.sll_addr[2] = 0x0C;

              dest_addr.sll_addr[3] = 0x00;

              dest_addr.sll_addr[4] = 0x95;

              dest_addr.sll_addr[5] = 0x02;



              return sendto(info->sock_fd, buf, length, 0, (struct sockaddr*) &dest_addr, sizeof(struct sockaddr_ll));

        }

I was unable to capture the packet using wireshark. After tryiing too many things, I found out that buffer used to send should have all ethernet frame fields (starting from destination address). When I added the destination and source address and other ethernet fields into the buffer, I was able to capture the packet using wireshark. So the send function doesn't use the MAC address stored in `dest_addr.sll_addr`.

My question is, Then what's the need of `sll_addr` field in the `struct sockaddr_ll`? Manuals say that it is the destination MAC address.