controlpush is a program that is part of the EPICS support package. It uses a configuration file to connect to a set of EPICS channels, connects to some TCP/IP server and then sends Tcl commands to that server to maintain a set of Tcl arrays that allow the server process to maintain a copy of the state of those channels, their units and when their values were last updated.
controlpush is descsribed fully in: the controlpush manpage.
The intent is that controlpush be pointed at a TclServer. The TclServer is a wish shell extended with the ability to accept commands from TCP/IP connected clients.
You can use controlpush in conjunction with TclServer and application specific scripts to provide a visual display of control system parameters. epicsdisplay is an example of this technique. Another typical use of controlpush is in conjunction with readout skeletons that support tclserver functionality to provide a set of data in the event stream that logs the control system parameters and their changes throughout the run.
controlpush Maintains information in arrays that are indexed by channel name:
EPICS_DATA(channelName)
Is the most recently received update for
channelName.
EPICS_UNITS(channelName)
Are the engineering units for
channelName
EPICS_UPDATED(channelName)
Is the timestamp of the alst update received for
channelName.