Check if user exists using id (linux)

I see a lot of examples about check if user exists in *nix system using id

• Find out if user name exists
• Check Whether a User Exists

For test my code i've create a simple code and after check and verify work I've copied to develop script

checkuser.sh

#!/usr/bin/env bash function checkUser() { if id "$USER" >/dev/null 2>&1; then echo "user exists" else echo "user does not exist" fi } USER=$4 checkUser 

Test code

sudo local/checkuser.sh misitio test 7.3 abkrim /home/abkrim/Sites/ abkrim.EXISTS user exists 

But when copy in my script not work

#!/usr/bin/env bash if [ $EUID != 0 ]; then sudo "$0" "$@" exit $? fi SITE=$1 PHP=$3 USER=$4 NGINX=/etc/nginx/ FPM=/etc/php/${PHP}/fpm/pool.d/ PATH=$5 checkUser 

Test code

sudo local/deploy_site.sh misitio test 7.3 abkrim /home/abkrim/Sites/ abkrim user does not exist 

1 Answer

PATH is in the environment, it is special. After your script does PATH=$5, it's no longer able to find the id executable; therefore this

id "$USER" >/dev/null 2>&1 

silently fails.

You probably do not want to overwrite PATH. You probably want your variables in lower case.

However if you really want to overwrite PATH, then you should later use full path to any executable that shouldn't depend on the new ("custom") PATH. E.g. /usr/bin/id.