Bash script to check running process [duplicate]

I wrote a bash-script to check if a process is running. It doesn't work since the ps command always returns exit code 1. When I run the ps command from the command-line, the $? is correctly set, but within the script it is always 1. Any idea?

#!/bin/bash
SERVICE=$1

ps -a | grep -v grep | grep $1 > /dev/null
result=$?
echo "exit code: ${result}"
if [ "${result}" -eq "0" ] ; then
    echo "`date`: $SERVICE service running, everything is fine"
else
    echo "`date`: $SERVICE is not running"
fi

Bash version: GNU bash, version 3.2.25(1)-release (x86_64-redhat-linux-gnu)

Solution 1:

There are a few really simple methods:

pgrep procname && echo Running 
pgrep procname || echo Not running 
killall -q -0 procname && echo Running 
pidof procname && echo Running

Solution 2:

This trick works for me. Hope this could help you. Let's save the followings as checkRunningProcess.sh

#!/bin/bash
ps_out=`ps -ef | grep $1 | grep -v 'grep' | grep -v $0`
result=$(echo $ps_out | grep "$1")
if [[ "$result" != "" ]];then
    echo "Running"
else
    echo "Not Running"
fi

Make the checkRunningProcess.sh executable.And then use it.
Example to use.

20:10 $ checkRunningProcess.sh proxy.py
Running
20:12 $ checkRunningProcess.sh abcdef
Not Running