Post-M6 - restore X,Y ?

I have a rack-based toolchanger/toolsetter at the back of my CNC router.  My custom M6 gcode saves the X,Y location at the start, and moves back there at the end (at max Z, of course).  Often the next thing that happens is a rapid to a different X,Y.  I'm wondering if there's a safe way to not restore the position after the M6, or if there's some magic to restore it only if the next move is anything other than a G0XnYn move (i.e. G1 or G0Zn)?

There is no magic as far as I know....
Is this not something you can deal with in the post-processor?
Like Ssetting a global before the M6, e.g. #<_restore_xy> = 0, and have your M6 read that flag to decide whether to restore?

Linuxcnc architecture will fight you hard on this, no real way to know the future move type after an M6, preview does it, but is fragile, it would be a waste of time implementing something like that IMO

Yeah, I didn't think there would be any magic, but I figured I'd ask. My files come from various sources so "do it in post" is not reliable enough unless EVERY post does a G0XY before any GZ.

djdelorie wrote:

or if there's some magic to restore it only if the next move is anything other than a G0XnYn move (i.e. G1 or G0Zn)?

You could consider adding the required magic with a Gcode filter that is applied when files are opened...

I could do that, but keeping track of the old Z might be tricky, especially if subroutines are involved.
I was also thinking that wrapping the "G0" and "G1" gcodes in a short python script (or even gcode wrapper) might work, but it would take more time than I waste waiting for the machine
I guess what I was originally asking was "does everyone else do it this way too?"

I don't think moving back to the original position after an M6 is standard practice, all post should have safe move inserted after a tool change, this is not something dealt with on the machine side IMO
If your post expects the tool change to happen and the machine to not have moved and does not give you a way to implement safety moves to re-approach the work-piece after a tool change, this is just bad design of the CAM/Post the fix should be there IMO