command to check file path is valid or not linux code example

Example 1: linux command if directory exists

DIR="/etc/httpd/"
if [ -d "$DIR" ]; then
  ### Take action if $DIR exists ###
  echo "Installing config files in ${DIR}..."
else
  ###  Control will jump here if $DIR does NOT exists ###
  echo "Error: ${DIR} not found. Can not continue."
  exit 1
fi

Example 2: .sh script: check if file exist

#!/bin/bash
if [ -e x.txt ]
then
    echo "ok"
else
    echo "nok"
fi