Have you ever wanted to read about a system variables current settings without going to the online Help or how to save and restore system variables on your or another machine? In this quick article I will explain the Express Tool System Variable Editor just to show you what it does.
You must have the AutoCAD Express Tools installed to use this tool.
The System Variable Editor allows you to view, edit and save system variable settings.
Express menu: Tools > System Variable Editor
AutoCAD Command line: SYSVDLG 
The dialog shows you the entire list of AutoCAD system variables. You can review and change values and search with filters such as *DIM will show all system variables that start with DIM. The best use of this tool is to save a file with all of your current system variable settings. You can then restore the system variables on this or other machines.
Initial Value Displays the initial value of the system variable highlighted in the list box. This is the value the system variable has in a new drawing.
Saved In Displays where the value of the highlighted system variable is saved.
Type Displays the type of the highlighted system variable; for example, integer, real, or string.
You can save the system variable settings using the Save button and then save to a SVF or even a SCR script that can be ran from the AutoCAD command line. You can save all, filtered, or a selected list (highlighted) of system variables. If you saved the output to a SVF file, you can use the Read button from the System Variable Editor to read in an restore the system variables.
From the System Variable Editor Help:
No changes are saved to the drawing until you choose OK. All pending changes can be discarded with the Cancel button. SYSVDLG will validate new system variable values as they are changed.
Two files, defaults.svf and defaults.scr, are installed in the Express directory along with the System Variable Editor. These files contain AutoCAD's the default system variable settings for a new installation of AutoCAD. To return AutoCAD to a 'pristine' system variable state you can either read the defaults.svf file into SYSVDLG or run the defaults.scr file from the AutoCAD command line using the SCRIPT command. Be aware that this will overwrite any system variable settings in the drawing you are currently editing.
Cheers,
-Shaan
Oldie but a goodie from this blog 8/10/04
