Linux Shell脚本，用于从列表中为用户添加密码

Question

I'm trying to modify a script that read usernames/password from a file which is like this:

user1 pass1
user2 pass2
user3 pass3

I can't get the script to read the space between the users and pass. What can I use to delimit this space? This is my code:

for row in `cat $1`
do
  if [ $(id -u) -eq 0 ]; then


      username=${row%:*}
      password=${row#*:}
      #echo $username
      #echo $password

I know I have to change the stuff in ${row%: } and ${row%: }

What do I have to put so it sees the space between user1 pass1 ?

Answer 1

It would be easier to split the two fields as you read each line. You can do that with read . It's also better to use a while loop here (a for loop requires to play with $IFS and it would also load the entire file in memory):

#!/bin/bash
if [ "$EUID" -ne 0 ]; then
    echo >&2 "You are not root"
    exit 1
fi

while read -r username password; do
    # do the useradd stuff here
done < "$1"

Notice that I also changed $(id -u) to $UID which should be faster since it does not invoke an external program.