usage="stop         -- stop pipeline\
\
Usage:\
    stop <pid>...\
    stop -h | --help\
\
Options:\
    -h --help   Show this message.\
    <pid>       Pipeline id, obtained from ps\
"

if ! docopt $usage $*; then
    exit false
fi

for i in $pid; do echo 'stop' >/proc/$i/ctl; done
