shell script respond to keypress

bash shell input keypress
j0h picture j0h · Jun 3, 2014 · Viewed 42.8k times · Source

I have a shell script that essentially says something like 

while true; do
    read -r input
    if ["$input" = "a"]; then 
        echo "hello world"           
    fi
done

That is all well, and good, but I just realized having to hit ENTER presents a serious problem in this situation. What I need is for the script to respond when a key is pressed, without having to hit enter.

Is there a way to achieve this functionality within a shell script?

Answer

pacholik picture pacholik · Jun 3, 2014 
read -rsn1

Expect only one letter (and don't wait for submitting) and be silent (don't write that letter back).

Related questions

How to concatenate string variables in Bash

In PHP, strings are concatenated together as follows: $foo = "Hello"; $foo .= " World"; Here, $foo becomes "Hello World". How is this accomplished in Bash?

Read More
How can I check if a directory exists in a Bash shell script?

What command can be used to check if a directory exists or not, within a Bash shell script?

Read More
How do I split a string on a delimiter in Bash?

I have this string stored in a variable: IN="[email protected];[email protected]" Now I would like to split the strings by ; delimiter so that I have: ADDR1="[email protected]" ADDR2="[email protected]" I don't necessarily …

Read More