sed命令

    把/home/visi/test.txt中的visi替换成ruci

    sudo sed -i 's/visi/ruci/' /home/visi/test.txt

    在文件/home/visi/test.txt中追加server 10.241.19.2

    sudo echo "server 10.241.19.2" >> /home/visi/test.txt