Linux systems write shell scripts to batch create and delete users

First, write shell scripts to add users in bulk

Implementation method: To determine whether the user exists, there is a return error prompt, while determining whether the user file exists, does not exist then exit

1. Create Add User Script

[Email protected] ~]# vim useradd.sh
#!/bin/bash
If [$#-eq 0];then
echo "You didn't enter any files!"
Exit 1
Fi

if [!-F $];then
echo "Wrong input! "
Exit 2
Fi

For user in ' cat $ '
Do
ID $user &>/dev/null
If [$?-eq 0];then
echo "User $user already exists! "
Else
Useradd-s/sbin/nologin $user
echo "Password" | passwd--stdin $user
echo "User $user created successfully. "
Fi
Done

2. Check the script and add executable permissions

[Email protected] ~]# sh-n useradd.sh
[Email protected] ~]# chmod +x useradd.sh

3. Add Users

[Email protected] ~]#./useradd.sh
You did not enter any files!
[Email protected] ~]#/useradd.sh user.txt
Change the password for the user user1.
PASSWD: All the authentication tokens have been successfully updated.
User User1 created successfully.
Change the password for the user user2.
PASSWD: All the authentication tokens have been successfully updated.
User User2 created successfully.
Change the password for the user User3.
PASSWD: All the authentication tokens have been successfully updated.
User User3 created successfully.
Change the password for the user user4.
PASSWD: All the authentication tokens have been successfully updated.
User User4 created successfully.
Change the password for the user user5.
PASSWD: All the authentication tokens have been successfully updated.
User User5 created successfully.

Second, delete the user

1. Write the Delete script

[Email protected] ~]# vim userdel.sh

#!/bin/bash
#userdel
If [$#-eq 0];then
        echo "You didn't enter the file! "
        exit 1
Fi

if [!] -F "$"];then
        echo "wrong input! "
        exit 2
Fi

for user in ' cat $ '
do
         ID $user &>/dev/null
        if [$-eq 0];then
                Userdel-r $user &>/dev/null
                 echo "Delete $user success!
        Else
                 echo "user does not exist! "
        fi
Done

[Email protected] ~]# sh-n userdel.sh
[Email protected] ~]# chmod a+x userdel.sh

2. Delete users

[Email protected] ~]#/userdel.sh 111
Wrong input!
[Email protected] ~]#/userdel.sh user.txt
Delete User1 success!
Delete User2 success!
Delete User3 success!
Delete User4 Success!
Delete User5 success!
[Email protected] ~]#/userdel.sh user.txt
User does not exist!
User does not exist!
User does not exist!
User does not exist!
User does not exist!

While read user
Do
ID $user &>/dev/null
If [$?-eq 0];then
echo "User $user already exists! "
Else
Useradd-s/sbin/nologin $user
echo "Password" | passwd--stdin $user
echo "User $user created successfully. "
Fi
Done < $

Linux systems write shell scripts to batch create and delete users