If a process is running

shell-proc.sh

#!/bin/sh

PROC_HOME=$(cd "$(dirname "$0")"; pwd)
PID_FILE=$PROC_HOME/hello.pid

function alive() {
    if [ -f ${PID_FILE} ] && ((`ps awux | grep -v grep | grep -c chrome`)); then
        echo "the process is running"
        exit 1
    fi
    echo "the process not running"
}

case "$1" in
    alive)
        alive
    ;;

    *)
        echo "Usage: $0 {alive}"
    ;;
esac

exit 0

# http://blog.163.com/crane02@126/blog/static/52055236201061781932562/
# if you use '#!/bin/sh' in ubuntu, an error is thrown out 'Syntax error: "(" unexpected'
# but if  '#!/bin/sh', everything is ok
# maybe I use some features only bash has in this snippet