2018/03/05

March 05 2018 Monday

Weather：little rain to cloudy
1、需求：编写一个名为chname的程序，将当前目录下所有的.txt文件更名为.doc文件。
2、需求：编写一个名为chuser的程序，执行中每隔5分钟检查指定的用户是否登录系统，用户名从命令行输入；如果指定的用户已经登录，则显示相关信息。

[root@Dasoncheng sbin]# cat chname.sh 
#!/bin/bash
##Changing the name of file likes .txt to .doc!
for i in `find . -maxdepth 1 -name "*.txt" -type f `;
do
  i2=`echo $i |awk -F '.txt' '{print $1}'`
  mv $i $i2.doc
done 

[root@Dasoncheng sbin]# cat o.sh 
#!/bin/bash
##2.Test the user who i read whether is online every five miniutes !
read -p "Please input a username !" n
while :
do
  if `who |grep -w $n &>/dev/null`;
  then
      echo "The user $n is online !"
  else
      echo "Sorry , the user $n is offline !"
  fi
  sleep 300
done

answer referred

1
#!/bin/bash
find . -type f -name "*.txt" > /tmp/txt.list
for f in `cat /tmp/txt.list`
do
    n=`echo $f|sed -r 's/(.*)\.txt/\1/'`
    echo "mv $f $n.doc"
done

2 
#!/bin/bash
read -p "Please input the username: " user
while :
do
    if who | grep -qw $user
    then
        echo $user login.
    else
        echo $user not login.
    fi
    sleep 300
done