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csocketsnetwork-programmingdata-stream

View socket data header?

After accepting data from a socket, can I view the header for the data? I want to know what IP address the packet was sent to as I am listening on multiple interfaces.

Solution

  • You can use getsockname to fetch the local IP address of the socket.

    int getsockname(int socket, struct sockaddr *restrict address,
       socklen_t *restrict address_len);

    Here is an example:

    struct sockaddr_in addr;
socklen_t len = sizeof(addr);
memset(&addr, 0, sizeof(addr));

getsockname(s, &addr, &len);