It can be done. Early S3D gcode used to do that. No one liked it much. And,
indeed, S3D had to stop doing it as it triggered a known, long standing bug
in MakerBot's branch of their firmware. (I had reported the bug along with the
fix back in 2011 and again a couple of times in 2012. They never saw fit to
fix it. It was a buffer overrun.)
At any rate, see
http://replicat.org/mcodes
I believe you want M70
Dan