tcpclo - DTN TCPCL-compliant convergence layer adapter output task

       Report bugs to <ion-bugs@korgano.eecs.ohiou.edu>

tcpclo is a background "daemon" task that connects to a remote node's TCP socket at remote_hostname and
       remote_port_nbr.  It sends a contact header, and it records the acknowledgement flag, reactive
       fragmentation flag and negative acknowledgements flag in the contact header it receives from its peer
       tcpcli task.  It then begins extracting bundles from the queues of bundles ready for transmission via TCP
       to this remote bundle protocol agent and transmitting those bundles over the connected socket to that
       node.  Each transmitted bundle is preceded by message type, segmentation flags, and an SDNV indicating
       the size of the bundle (in bytes).

       If not specified, remote_port_nbr defaults to 4556.

       Note that tcpclo is not a "promiscuous" convergence layer daemon: it can transmit bundles only to the
       node to which it is connected, so scheme configuration directives that cite this outduct need only
       provide the protocol name and the outduct name as specified on the command line when tcpclo is started.

       tcpclo is spawned automatically by bpadmin in response to the 's' (START) command that starts operation
       of the Bundle Protocol, and it is terminated by bpadmin in response to an 'x' (STOP) command.  tcpclo can
       also be spawned and terminated in response to START and STOP commands that pertain specifically to the
       TCP convergence layer protocol.

       The following diagnostics may be issued to the ion.log log file:

       tcpclo can't attach to BP.
           bpadmin has not yet initialized Bundle Protocol operations.

       No such tcp duct.
           No TCP outduct with duct name matching remote_hostname and remote_port_nbr has been added to  the  BP
           database.   Use bpadmin to stop the TCP convergence-layer protocol, add the outduct, and then restart
           the TCP protocol.

       CLO task is already started for this duct.
           Redundant initiation of tcpclo.

       Can't get IP address for host
           Operating system error.  Check errtext, correct problem, and restart TCP.

       No environment variables apply.

       "0" tcpclo  terminated  normally,  for  reasons  noted  in the ion.log file.  If this termination was not
           commanded, investigate and solve the problem identified in the log file and use  bpadmin  to  restart
           the TCPCL protocol.

       "1" tcpclo  terminated  abnormally,  for  reasons  noted  in the ion.log file.  Investigate and solve the
           problem identified in the log file, then use bpadmin to restart the TCPCL protocol.

       No configuration files are needed.

       tcpclo - DTN TCPCL-compliant convergence layer adapter output task

bpadmin(1), bprc(5), tcpcli(1)

perl v5.24.1                                       2016-07-07                                          TCPCLO(1)

tcpcloremote_hostname[:remote_port_nbr]