Thanks That’s what I figured was happening.

I wasn’t sure if I should start a new thread for the pen up / pen down stuff:

I can’t control the pen up / pen down from the cli using raspian on a raspberry pi.

“Axidraw -M pen_up” requests a filename in order to work, but when I include a filename, it tries to plot the file (as you might expect). Same with pen down. I just want to adjust the pen height without moving the pen from home position.

I suppose I can install Inkscape and axidraw extensions on the pi and adjust from there, but that has its own set of self inflicted problems:
I won’t muddy the waters with those issues here.