After the putty is cut off, the program is still running (linux)

For Unix and Linux servers, ssh is often used for maintenance. Some operations are time-consuming, such as updating programs. If you disconnect the ssh connection, the update program will be interrupted. How can we ensure that the update process is still running after ssh is disconnected? There are two methods: (1) nohup # nohup Application name & after that, if you disconnect ssh, the program will still run. The disadvantage of this method is that the application does not have an interactive interface, and the output of the program will output a xxx. out file, and it cannot end in the interface control program in the future. It must be killed. This method is very rude and rarely used. (Http://www.my400800.cn) (2) screen # screen press enter to enter the Screen subinterface, at this time putty title bar will indicate that in the subinterface status, then run your program # Application name, press Ctrl + A, and then press d. switch back to the main interface, and the Putty window title bar will also indicate. # Perform other operations or exit. At this time, ssh is disconnected and the program is still running. After reconnecting to the ssh service, enter # screen-ls to view the code of the sub-interface. Then, enter the # screen-r code to view the sub-interface where your program was originally running.