VMS Help TCPIP Services, Programming Interfaces, Sockets API, sendto(), Errors  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    EAFNOSUPPORT       Addresses in the specified address family
                       cannot be used with this socket.
    EBADF              The socket descriptor is invalid.
    ECONNRESET         A connection was forcibly closed by a peer.
    EDESTADDRREQ       You did not specify a destination address for
                       the connectionless socket and no peer address
                       is set.
    EFAULT             An invalid user space address is specified for
                       a argument.
    EHOSTUNREACH       The destination host is unreachable.
    EINTR              A signal interrupted sendto() before any data
                       was transmitted.
    EINVAL             The dest_len argument is not a valid size for
                       the specified address family.
    EISCONN            The connection-oriented socket for which a
                       destination address was specified is already
                       connected.
    EMSGSIZE           The message is too large to be sent all at
                       once, as the socket requires.
    ENETDOWN           The local network connection is not
                       operational.
    ENETUNREACH        The destination network is unreachable.
    ENOBUFS            The system has insufficient to complete the
                       call.
    ENOMEM             The system did not have sufficient memory to
                       fulfill the request.
    ENOTCONN           The socket is connection-oriented but is not
                       connected.
    ENOTSOCK           The socket descriptor is invalid.
    EOPNOTSUPP         The socket argument is associated with a
                       socket that does not support one or more of
                       the values set in flags.
    EPIPE              The socket is shut down for writing or is
                       connection oriented, and the peer is closed or
                       shut down for reading. In the latter case, if
                       the socket is of type SOCK_STREAM, the SIGPIPE
                       signal is generated to the calling process.
    EWOULDBLOCK        The socket is marked nonblocking, and no space
                       is available for the sendto() function.