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The dd_link between DD Systems

The program dd_link allows to link two DD systems over the network. Its syntax is: 

 
 dd_link from_dd to_dd <attach_mode_file>


where: 		 from_dd 		 the DD system from where the events are retrieved,


		  to_dd 		 the DD system to where the events are being sent


		  attach_mode_file 		 an optional filename indicating in which mode


		 		  dd_link attaches to the  from_dd system.
Note: The from_dd, to_dd DD systems have to be defined in the file $DDD_CONFIGURATION_FILE.

It required that dd_link starts runs on the host, where from_dd resides. It creates a fifo named ``->to_dd''. By default it attaches in sleep wait mode and retrieves events ONREQ basis. No event selection is done. This can be changed by specifying the optional parameter <attach_mode_file> (see $DD_DATA/dd_link_conf1 as an example).

Upon succesful connection to the from_dd system (as a master), dd_link starts a server on the to_dd host which attaches to the INPUT_FIFO of the to_dd system (as a master).

{ dd_link should be considered as an example how one can connect two DD systems. Currently there are hooks for either transfer one event at a time ( do_dd_trf or a block mode do_dd_mtrf, in which many events are transfered at a time. The file $DD_INC/dd_link_util.h has the default definitions which can be changed according to everyone's flavor and taste.


Online software development
Thu Mar 14 10:35:53 EST 1996