When removing the command from Centos, use the tab to make the "sounds ".

In linux, the tab key may be at most one. Using tabs when using commands such as ls and cd can reduce many keyboard input. For example, to enter a directory with a long directory name, you may just need to input the first few characters, then, use the tab. The entire directory name is added. If there are several directories with the same names in front, it will also prompt that some systems will generate a beep. If you do not like this sound, you can modify the configuration to remove it. Use vi to edit the/etc/inputrc file, remove the # sign before "set bell-style none", and restart the system!