Bash script to check running process [duplicate]

Answer 1

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

Answer 2

I found the problem. ps -ae instead ps -a works.

I guess it has to do with my rights in the shared hosting environment. There's apparently a difference between executing "ps -a" from the command line and executing it from within a bash-script.

Answer 3

A solution with service and awk that takes in a comma-delimited list of service names.

First it's probably a good bet you'll need root privileges to do what you want. If you don't need to check then you can remove that part.

#!/usr/bin/env bash

# First parameter is a comma-delimited string of service names i.e. service1,service2,service3
SERVICES=$1

ALL_SERVICES_STARTED=true

if [ $EUID -ne 0 ]; then
  if [ "$(id -u)" != "0" ]; then
    echo "root privileges are required" 1>&2
    exit 1
  fi
  exit 1
fi

for service in ${SERVICES//,/ }
do
    STATUS=$(service ${service} status | awk '{print $2}')

    if [ "${STATUS}" != "started" ]; then
        echo "${service} not started"
        ALL_SERVICES_STARTED=false
    fi
done

if ${ALL_SERVICES_STARTED} ; then
    echo "All services started"
    exit 0
else
    echo "Check Failed"
    exit 1
fi

Answer 4

A simple script version of one of Andor's above suggestions:

!/bin/bash

pgrep $1 && echo Running

If the above script is called test.sh then, in order to test, type: test.sh NameOfProcessToCheck

e.g. test.sh php

Answer 5

I need to do this from time to time and end up hacking the command line until it works.

For example, here I want to see if I have any SSH connections, (the 8th column returned by "ps" is the running "path-to-procname" and is filtered by "awk":

ps | awk -e '{ print $8 }' | grep ssh | sed -e 's/.*\///g'

Then I put it in a shell-script, ("eval"-ing the command line inside of backticks), like this:

#!/bin/bash

VNC_STRING=`ps | awk -e '{ print $8 }' | grep vnc | sed -e 's/.*\///g'`

if [ ! -z "$VNC_STRING" ]; then
    echo "The VNC STRING is not empty, therefore your process is running."
fi

The "sed" part trims the path to the exact token and might not be necessary for your needs.

Here's my example I used to get your answer. I wrote it to automatically create 2 SSH tunnels and launch a VNC client for each.

I run it from my Cygwin shell to do admin to my backend from my windows workstation, so I can jump to UNIX/LINUX-land with one command, (this also assumes the client rsa keys have already been "ssh-copy-id"-ed and are known to the remote host).

It's idempotent in that each proc/command only fires when their $VAR eval's to an empty string.

It appends " | wc -l" to store the number of running procs that match, (i.e., number of lines found), instead of proc-name for each $VAR to suit my needs. I keep the "echo" statements so I can re-run and diagnose the state of both connections.

#!/bin/bash

SSH_COUNT=`eval ps | awk -e '{ print $8 }' | grep ssh | sed -e 's/.*\///g' | wc -l`
VNC_COUNT=`eval ps | awk -e '{ print $8 }' | grep vnc | sed -e 's/.*\///g' | wc -l`

if  [ $SSH_COUNT = "2" ]; then
    echo "There are already 2 SSH tunnels."
elif  [ $SSH_COUNT = "1" ]; then
    echo "There is only 1 SSH tunnel."
elif [ $SSH_COUNT = "0" ]; then
    echo "connecting 2 SSH tunnels."
    ssh -L 5901:localhost:5901 -f -l USER1 HOST1 sleep 10;
    ssh -L 5904:localhost:5904 -f -l USER2 HOST2 sleep 10;
fi

if  [ $VNC_COUNT = "2" ]; then
    echo "There are already 2 VNC sessions."
elif  [ $VNC_COUNT = "1" ]; then
    echo "There is only 1 VNC session."
elif [ $VNC_COUNT = "0" ]; then
    echo "launching 2 vnc sessions."
    vncviewer.exe localhost:1 &
    vncviewer.exe localhost:4 &
fi

This is very perl-like to me and possibly more unix utils than true shell scripting. I know there are lots of "MAGIC" numbers and cheezy hard-coded values but it works, (I think I'm also in poor taste for using so much UPPERCASE too). Flexibility can be added with some cmd-line args to make this more versatile but I wanted to share what worked for me. Please improve and share. Cheers.

Answer 6

Those are helpful hints. I just needed to know if a service was running when I started the script, so I could leave the service in the same state when I left. I ended up using this:

   HTTPDSERVICE=$(ps -A | grep httpd | head -1)

   [ -z "$HTTPDSERVICE" ] &&  echo "No apache service running."