The command is -DWGUNITS and not INSUNITS or LUNITS.

Please pay more attention before responding.

-DWGUNITS is a command.

INSUNITS and LUNITS are system variables

As others have pointed out, -DWGUNITS looks to be related to an AutoCAD Vertical. It's not documented anywhere that I could find in the HELP. Also, from other posts it seems geared more towards converting a drawing from one set of units to another. Further to this, the prompting of the command changes depending on whether you've run the command previously in a drawing. So simply calling
may not work in all cases.

If you're simply trying to set the drawing units, then it would be better to explore the -UNITS command.

How to do it without COMMAND to look elegant within a program?

All the settings of the -UNITS command can be set via a system variable, which allows you to avoid making a command call from lisp. This is a more elegant approach. e.g

I mod. CAB's version in spare time...
I added GrSnap and few other options - calling OSNAP command during dragging...

Here is the link : https://forums.autodesk.com/t5/visual-lisp-autolisp-and-general/need-help-to-modify-code-quot-rotate-block-for-preview-prior/m-p/12782519/highlight/true#M466237

How to modify the value in -DWGUNITS from 3 to 6 by AutoLISP?

Command: -DWGUNITS

Drawing units:
  1. Inches
  2. Feet
  3. Millimeters
  4. Centimeters
  5. Decimeters
  6. Meters
Unit for length <3>: 6

This part of the command relates to INSUNITS
https://help.autodesk.com/view/ACDLT/2025/ENU/?guid=GUID-A58A87BB-482B-4042-A00A-EEF55A2B4FD8

PKENEWELL has listed this and the other system variables related to this command.

Quote from: ScottMC on April 26, 2024, 09:55:58 AM

With my ancient A2K, this works: (setvar "LUNITS" 2) <- for decimal

Untested but?

Code: [Select]

(defun check-and-set-lunits ()
  (if (/= (getvar "LUNITS") 6) ; Check if LUNITS is not already set to 6
      (progn
        (setq change_units (strcat "\nLUNITS is currently set to " (itoa (getvar "LUNITS")) ", do you want to change it to 6? [Y/N]: "))
        (if (equal (getstring change_units) "Y")
            (setvar "LUNITS" 6) ; Change LUNITS to 6
            (prompt "\nLUNITS remains unchanged.")))))
           
(check-and-set-lunits)

Change for meters

The command is -DWGUNITS and LUNITS does not accept =6

You're more than welcome Lonnie - I'm delighted that it's still proving useful!