linux - shell创建用户，报错“passwd: Unknown user name '}''.”

Question

思路：
判断用户是否存在，标记flag
存在，修改用户密码
不存在，创建用户并修改密码

---

#!/bin/bash
#the script act on a batch of add user,username at the same password 
name="admin"
password="demo"
userList="cat /etc/passwd | awk -F ':' '{print $1}'"
flag=false
for name in $userList; do
    #statements
    flag=true
done
if [ $flag=true ]; then
    #change password
    echo "user exist"
else
    echo "create user admin"
    useradd /home/$name $name
fi
echo "change password to demo"
echo $password | passwd --stdin $name
echo "succeed"

---

输出如下：

---

实际：
用户不存在且没有创建成功

Answer 1

Wouldn’t it be more convenient to use the id command to determine?

id admin >& /dev/null
if [ $? -ne 0 ]
then
#不等于0，创建用户
    echo "create user admin"
    useradd -d /home/admin -m admin
else
#等于0说明用户已经存在
    echo "user exist"
fi

Note that your useradd specifies the home directory parameter, otherwise the execution will be unsuccessful.
And to determine whether the user exists in /etc/passwd, you can also use:

grep admin /etc/passwd >& /dev/null;echo $?

See if it is equal to 0.

Answer 2

The reason why your user should include the } symbol