Check if a process is running using Bash

Question

I am trying to check if a process is running with the code below:

SERVICE=\"./yowsup/yowsup-cli\"
RESULT=`ps aux | grep $SERVICE`

if [ \"${RESULT:-null}\" =         


        

Answer 1

SERVICE="./yowsup/yowsup-cli"
RESULT=`ps aux | grep $SERVICE|grep -v grep`

if [ "${RESULT:-null}" = null ]; then
    echo "not running"
else
    echo "running"
fi