Undo locked in loop?

[BillZ]

R2004:
Has anyone else had this problem?
When I run a lisp routine that uses "undo" "BE" and then at the end of the program "undo" "END" it seems afterwards that if I try to manuall use the "U" command at the command line, I am trapped in an eternal toggle that won't let me return to a previous step or two or three from where the program ended.
This is what I get when I enter u at the comman line.
Command: u
(Lisp Expression)
Command: u
GROUP
Command: u
(Lisp Expression)
Command: u
GROUP
Command: u
(Lisp Expression)
Command: u
GROUP
Command: u
(Lisp Expression)
Command: u
GROUP
Command: u
(Lisp Expression)
Command: u
GROUP
Command: u
(Lisp Expression)
Command: u
GROUP
Command: u
(Lisp Expression)
Command: u
GROUP
Command: u
(Lisp Expression)
Command: u
GROUP
I go nowhere until I use undo back or some other option.
What is going on?

TIA

Bill

[BillZ]

FWIW:
This may or may not have anything to do with the undo BE and END.
After I run that program I can undo normally one step at a time.
If I run another program immediately afer the first program that uses multiple grvec calls to display a cutter path, then the u function is rendered usless.

Bill

[BillZ]

This is the program that is giving the trouble.
See if you can duplicate it on R2004.
Draw pline (heavy style) for a tool path and pick the pline at the command prompt.
Thanks

Bill

[BillZ]

Whoops forgot the dcl so here it is.

Bill

[BillZ]

I gues I'd better include the dwg because it only does it on the frame recess paths (the square green paths around the door holes).

Bill

[BillZ]

The more I look at this, AutoCAD is performing an undo for each grvec call. If the list fed to grvec is 100 items long then the undo actually "undoes" each set of points call to grvecs.

Weird. Didn't do that in R14.

Bill

[Anonymous]

That's what I thought, I was a little suspicious that it wasn't a loop but rather alot of records in the undo section to work thru. They must have added grvecs actions to the undo record for some reason (which I can't quite figure out why at this point, since nothing is created or altered).

[BillZ]

Yeah, It took me a while to figure it out.
I finally opened the drawing and did one zoom window and ran the grvecs program. Had to undo for a minute or so before the zoom reversed to where it was when I started.


Bill

[Anonymous]

I have a universal function that I use for dragging that uses grvecs extensively. I guess I'll just have to forget about the undo after using it. Bummer 😞

[BillZ]

Not exactly,
Just wrap a undo BE and undo END around the grvecs program.

Worked for me. 8^)

Bill

[Anonymous]

Right!