udp

Tnm::udp(n)                     Tnm Tcl Extension                    Tnm::udp(n)



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NAME
       Tnm::udp - Send and receive UDP datagrams.
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DESCRIPTION
       The Tnm::udp command allows to send and receive datagrams using the User
       Datagram Protocol (UDP) (RFC 768).


UDP COMMAND
       Tnm::udp open [port]
              The Tnm::udp open command opens a UDP datagram socket and returns
              a handle. The socket is bound to a given port number or name. An
              unused port number is used if the port argument is missing.

       Tnm::udp connect host port
              The Tnm::udp connect command opens a UDP datagram socket and
              connects it to a port on a remote host. A connected UDP socket
              only allows to send messages to a single destination. This usually
              allows to shorten the code since there is no need to specify the
              destination address for each Tnm::udp send command on a connected
              UDP socket. The command returns a udp handle.

       Tnm::udp send handle [host port] message
              The Tnm::udp send command sends a datagram containing message to
              the destination specified by host and port. The host and port
              arguments may not be used if the UDP handle is already connected
              to a transport endpoint. If the UDP handle is not connected, you
              must use these optional arguments to specify the destination of
              the datagram.

       Tnm::udp receive handle
              The Tnm::udp receive command receives a datagram from the UDP
              socket associated with handle. This command blocks until a
              datagram is ready to be received. In most cases, it might be a
              good idea to check for pending datagrams using the Tnm::udp bind
              command.

       Tnm::udp close handle
              The Tnm::udp close command closes the UDP socket associated with
              handle.

       Tnm::udp bind handle readable [script]
       Tnm::udp bind handle writable [script]
              The Tnm::udp bind command allows to bind scripts to a UDP handle.
              A script is evaluated once the UDP handle becomes either readable
              or writable, depending on the third argument of the Tnm::udp bind
              command. The script currently bound to a UDP handle can be
              retrieved by calling the udp bind command without a script
              argument. Bindings are removed by binding an empty string.

       Tnm::udp info [handle]
              The Tnm::udp info command without the handle argument returns a
              list of all existing UDP handles. Information about the state of a
              UDP handle can be obtained by supplying a valid UDP handle. The
              result is a list containing the source IP address, the source
              port, the destination IP address and the destination port.


SEE ALSO
       scotty(1), Tnm(n), Tcl(n)


AUTHORS
       Juergen Schoenwaelder <schoenw@ibr.cs.tu-bs.de>



Tnm                               December 1997                      Tnm::udp(n)