/// @brief Send packet over specified socket.
///
+ /// This function will use local address specified in the @c pkt as a source
+ /// address for the packet and the interface index to select the index
+ /// through which the packet will be sent. However, if these values
+ /// are not specified for the packet (zero IP address and negative
+ /// interface index), this function will rely on the routing information
+ /// to determine the right outbound interface and source address.
+ ///
/// @param iface interface to be used to send packet
/// @param sockfd socket descriptor
/// @param pkt packet to be sent