Get the PID of a process

Many a times, one needs to get the PID of a process to do some additional tasks on it.
Here is a script which could be added into other scripts where you need such a requirement so as to kill a certain process if running, start a process if not found and many such cases!

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#!/bin/bash
#This script is to be used as ./testPID <processname>

PID=$(pgrep $@)
#if [ -z "$PID" ] is same as writing if[ "$PID" = "" ]
if [ "$PID" = ""  ]; then
  echo "Process not found"
else
    echo "Process[PID]: $@[$PID]"
fi

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