Runs `tilt up`, then `tilt down` upon interrupt

tilt-updown.sh

#!/bin/bash
#
# Wrap tilt so that a Ctrl-C will call `tilt down` when done.

tilt=
do_auto_down() {
    echo "Interrupt; killing $tilt"
    kill -INT $tilt
    tilt down
    exit 0
}

trap do_auto_down SIGINT

# Dup stdin and delegate to tilt
exec 3<&0
tilt up "$@" <&3 &

tilt=$!
wait $tilt