The RtFC depends on 4 distributed programs to transfer data from LBADR recordering systems to a central location, and then invoke the DiFX software correlator. ... control.pl: Connects all the perl processes together. ... Connects to control.pl. ... Connects to control.pl and corr.pl obs.pl runs an external programs (vsipack) to extract the requested time fragment from the (large) data files and optionally "compress" the data (select a sub selection of the data channels) before transferring. ...