clear

在terminal上操作时, 看见之前输入的N多命令记录,
像我一样的小小强迫症患者, 可以再输入clear命令, 然后回车.
而重度强迫症患者, 可以试试输入reset命令.

我们先来看看clear的介绍:

man clear 
#
NAME
       clear - clear the terminal screen

SYNOPSIS
       clear

DESCRIPTION
       clear  clears  your  screen if this is possible, including its scrollback buffer (if the extended "E3" capability is defined). 
       clear looks in the environment for the terminal type and then in the ter-minfo database to determine how to clear the screen.

       clear ignores any command-line parameters that may be present.

简而言之

clear没有参数, 那么clear ...后面加的任何参数会被忽略,然后照旧执行clear.
比如clear --help命令, 就没啥效果, 只能通过man clear命令来查看clear的介绍.
其次, clear操作后, 只是把终端屏幕翻到了新的一页, 所以可以通过拉动滚动条来查看历史内容.