HF scientific Online Data Acquisition System - Manual (Page 31)

Ref 22838 (8/02)
Rev 2.3
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5.0 Appendix
Lookout File Types
A Lookout process comprises of four files: Process (.l4p), State (.lst), Source
Code (.lks) and Security (.lka). These files are created automatically in the
application development cycle. All of the above files have the same user defined
file name (e.g. hfserver) but with file extension as indicated above. A brief
description of each file type and its function:
Process File: A process file is a compiled file that contains the Lookout process
that we want to run. Process files cannot be directly edited or modified. Rather,
Lookout compiles the .l4p on an object-by-object basis. The compilation occurs
whenever the application is saved. With this approach it is possible to create new
objects or modify existing ones without having to shut down the process, one of
the most powerful features of the Lookout SCADA system. Please note that in
order to be able to edit or modify a Lookout process it is necessary to have the
Keycode for the development version of Lookout loaded on the computer.
Source Code File: In the application development process, Lookout automatically
creates and updates a corresponding source code file when the File>>Save
command is invoked. The source code file is a standard ASCII text file that can be
viewed and printed with any word processor or text editor. The source code
information can be used for debugging and documentation.
State File: The state file contains the actual values of object data members.
Lookout uses the state file to store the position of switches, potentiometers, trend
lines etc. When Lookout first loads an application, it reads the state file to
determine what state the pots, switches, trend lines etc. should be upon startup.
The state file updates any time the application is saved or closed. It is also
updated on a periodic basis at user-defined intervals.
Security File: Every Lookout process has an attached security file identified by
the .lka extension. All the security information for a Lookout process is kept in
the .lka file.