LDEFS(OPCS) Optical Printer Control System LDEFS(OPCS) NAME ldefs - load OPCS definitions file USAGE ldefs filename.opc ldefs -c <command and args> EXAMPLES ldefs hicon.opc # load OPCSDEFS cmds from hicon.opc ldefs -c bigcounters nixie # use nixie counters ldefs -c ramp a 10 180 10 150 # redefine ramps for a chan DESCRIPTION This command allows the operator to load other definitions files. Users can make copies of the OPCSDEFS.OPC file, and make changes to the copy, then load this new copy with the LDEFS command to put the changes into effect. This avoids modification of the original OPCSDEFS.OPC file. One can also run single line OPCSDEFS commands with the '-c' flag, which interprets all arguments to the end of the line or a '!' character (see BANG(OPCS)) as OPCSDEFS commands. Example: ldefs -c bigcounters nixie ldefs -c name a Aerial name b Main name c Cam ! echo OK OPCSDEFS files contain special commands that setup the OPCS system's internal parameters. Use 'man -k OPCSDEFS:' for a listing of all the OPCSDEFS commands (such as the 'opcsdefs.opc' loaded on startup), or for any other files/commands used with LDEFS(OPCS). HISTORY The '-c' flag was added in OPCS version K2.00 to allow immediate execution of defs commands. In older releases to do the same, you had to first write commands into a temp file (e.g. using ECHO), then load that, e.g: ! echo bigcounters off > tmpfile ldefs tmpfile ! del tmpfile This trick is no longer needed in K2.xx, as you can use just 'ldefs -c bigcounters off' for the same effect. TRICKS WITH DEFS FILES People familiar with the IBM's operating system will be familiar with these capabilities... First, note that in K2.00 (and up), 'ldefs -c' can be used to run OPCSDEFS commands inside OPCS, e.g. ldefs -c bigcounters on # big counters Which makes many of the below techniques unnecessary extra work. However, in the older releases (K1.xx) this is not available so the below techniques must be used. As with all DEFS file commands, you can execute motor definition commands from within the OPCS software by creating a small file, and the loading commands from it via LDEFS(OPCS)... In the following example, we switch back and forth between large and small counters: ! echo bigcounters on > tmpfile ! ldefs tmpfile # big counters ! echo bigcounters off > tmpfile ! ldefs tmpfile # small counters This 'trick' can be used with any OPCSDEFS commands, and uses the operating system's ECHO command and 'reroute output' symbol (>) to create the file FOO, which is then loaded as a file with the LDEFS command. This technique CAN be used within a script or when entering commands manually. You can create multiline files from within a script as shown in this example using MSDOS's > and >> (append) symbols: ! echo flog 2.0 > tmpfile ! echo logcounters yes >> tmpfile ldefs tmpfile This technique can be programmed into run scripts, so defs file information can be changed on the fly. Here is another way to enter DEFS commands directly to the LDEFS command from within the OPCS software: ldefs con # Load the special MSDOS file CON... logcounters no # which is really the keyboard (console) ppr a 400 # reading these commands from keyboard ^Z # CTRL-Z and RETURN ends this mode.. cam 12 # ..back to OPCS commands The 'ldefs con' technique works well for interactive typing, but cannot be programmed into a script, since it always reads from the keyboard. Use the 'echo' technique listed in the previous example for programming DEFS commands into a running script. These techniques are actually standard ways of using the DOS operating system, and are not particular to just the OPCS software.. they can be used by any program running under MSDOS that properly supports the operating system. Users not familiar with these techniques should learn them only if they think they might need them. At very least, operators should be aware of this capability. SEE ALSO ECHO(OPCSDEFS) - disable echoing of defs commands OPCSCMD(OPCS) - run OPCS commands from within OPCSDEFS command mode man -k OPCSDEFS: - list OPCSDEFS commands with one line descripitions man -k OPCS: - list OPCS commands with one line descriptions ORIGIN Gregory Ercolano, Los Feliz California 11/29/89