Shell tips (134) simple keyboard input recorder

Realization effect ：

Run script , prompt 4 Characters .

In the input process , Not up to 4 Five characters before display .

Enter the first 4 After characters , Automatically display the entered 4 Characters .

#!/bin/bash
keypresses=4
old_tty_setting=$(stty -g) 
echo "Presss $keypresses keys"
stty -icanon -echo

keys=$(dd bs=1 count=$keypresses 2> /dev/null)
stty "$old_tty_setting"
echo "You pressed the \"$keys\" keys."
exit 0

 

Code brief description ：

stty -g Output stty Current settings , Stored in variables old_tty_setting in

stty -icanon -echo The standard input content will not be displayed on the terminal screen

dd bs=1 count=$keypresses 2> /dev/null There's no setup here if, Standard input will be used by default . Match the above stty Set up , Keyboard input is realized （ Standard input ） The content is dd Command to get , Stored in variable keys

stty "$old_tty_setting" Restore the original settings