shell script.从文件中获取用户名和密码添加用户

#在“/”下创建username和password两个文件，分别存放用户名和密码.格式为：username中每行一个用户名；password中每行一个密码，与username中的user一一对应。

#!/bin/bash

#判断文件是否存在
if [  ! -f /username ]; then
    echo "ERROR:file username unexistd"
elif [  ! -f /password ]; then
    echo "ERROR:file passwd unexistd"
else

#判断行数是否匹配
    NAMELINE=` wc -l /username |cut -d " " -f 1`
    PASSWDLINE=` wc -l /password |cut -d " " -f 1`
            if [ "$NAMELINE" = "0" -a "$PASSWDLINE" = "0" ];then

　　　　　　 echo "file username and password empty"

            elif [ "$NAMELINE" = "0" ]; then
                echo "file username empty"
               
            elif [ "$PASSWDLINE" = "0" ];then
                echo "file password empty"                 
               
            elif [ "$NAMELINE" != "$PASSWDLINE" ]; then
                echo "error,please check 'username' or 'passwd'"

　　　　#行数相等，创建用户
            elif [ "$NAMELINE" = "$PASSWDLINE" ]; then
                for num in $(seq 1 $NAMELINE)
                do
                    USERNM=`sed -n ${num}p /username`
                    PASSWD=`sed -n ${num}p /password`  
                    USERADD=`useradd $USERNM &> /dev/null && echo "1" || echo "0"`

　　　　　　　　#判断用户是否存在
                    if [ "$USERADD" = "1" ]; then  
                    echo $PASSWD|passwd --stdin $USERNM
                    echo "user $USERNM add successfully"
                    elif [ "$USERADD" = "0" ]; then
                    echo "useradd failed, user $USERNM existd" 
                    fi
                done
          fi
fi