Bash Shell Scripting - detect the Enter key

bash shell string-comparison enter
veda picture veda · Apr 10, 2010 · Viewed 57.7k times · Source

I need to compare my input with Enter/Return key... 

read -n1 key
if [ $key == "\n" ]
   echo "@@@"
fi

But this is not working.. What is wrong with this code

Answer

Mark Rushakoff picture Mark Rushakoff · Apr 10, 2010

Several issues with the posted code. Inline comments detail what to fix:

#!/bin/bash 
# ^^ Bash, not sh, must be used for read options

read -s -n 1 key  # -s: do not echo input character. -n 1: read only 1 character (separate with space)

# double brackets to test, single equals sign, empty string for just 'enter' in this case...
# if [[ ... ]] is followed by semicolon and 'then' keyword
if [[ $key = "" ]]; then 
    echo 'You pressed enter!'
else
    echo "You pressed '$key'"
fi

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