Check Whether a User Exists

Question

I want to create a script to check whether a user exists. I am using the logic below:

# getent passwd test > /dev/null 2&>1
# echo $?
0
# getent pa         


        

Answer 1

user infomation is stored in /etc/passwd, so you can use "grep 'usename' /etc/passwd" to check if the username exist. meanwhile you can use "id" shell command, it will print the user id and group id, if the user does not exist, it will print "no such user" message.