Function: comint-stop-subjob

Stop the current subjob.
This command also kills the pending input
between the process mark and point.

WARNING: if there is no current subjob, you can end up suspending
the top-level process running in the buffer. If you accidentally do
this, use M-x comint-continue-subjob to resume the process. (This
is not a problem with most shells, since they ignore this signal.) (fn)