SysVarLock reactor - lock variables from changes
------------------------------------------------
(C) 2006 CAD Studio, www.cadstudio.cz

Setup:
SysVarLock.VLX (LSP) and SysVarLock.TAB - must be copied into an AutoCAD directory
see SysVarLock.TAB for lockout definitions

SysVarLock.vlx (lsp) must be loaded into every AutoCAD document to protect the defined system
variables. You can load it automatically using ACAD.LSP/ACADDOC.LSP or with the _APPLOAD command.

Usage:
You can pre-define a table of variables to watch for attempted changes. If such variable is
to be modified, an optional expression is evaluated and if it evaluates to FALSE (= condition
is not met), that particular change of the variable value is not permitted (is reverted back).

The SysVarLock command can be used to disable/re-enable this functionality (ON/OFF options).
The 'List' option lists the watched variables. If you change the definition table you have to
reload the application or use the 'Reload' option. The 'Last action' option diplays the last
action of this reactor (variable allowed to change or reverted back).

NB:
- you cannot lock some internal variables like "REFEDITNAME"
- some variables do not fire the reactor mechanism when changed from another command (e.g. transparent):
 VIEWCTR VCMIN VIEWSIZE SCREENSIZE VSMIN VSMAX GRIDMODE GRIDUNIT SNAPUNIT SNAPSTYLE SNAPISOPAIR
 SNAPBASE SNAPANG CVPORT APERTURE PICKBOX ELEVATION CPROFILE CIRCLERAD
- you can temporarily set "sv:lockr-PRIVILEDGED" to T to override SysVarLock protection (e.g.
in your macros)

--------------------
CAD Studio a.s.
www.cadstudio.cz
info@cadstudio.cz
