Autocad versions

[derryck]

Hello. I would like to know, does Autocad change certain things from version to version, which cause lisp programs to stop working? If so what are the changes that we should be aware of?

Thanks

Derryck 

[scottbolton]

The most likely reason for lisp programs not working with newer version of AutoCAD is command line structure. For example, and this isn't an actual example:

A2004: (command "_chprop" ss "C" 1 "") ;changes the selection set colour to red;

A2011: (command "_chprop" ss "" "CO" 1 "")

For this reason I use as few (command statements as possible. Even (vl-cmdf will fail if the structure is changed, although the program won't crash at that point.

As far as documentation of these changes goes, hit F1 and read that!

Look into (entmake, (entmod, and (vl- commands. My tuppence.

S