How to search text stored in a variable?

Question

#!/bin/bash
num=$(gsettings get org.gnome.settings-daemon.plugins.media-keys custom-keybindings | grep -oE '[0-9]+'|sort -rn|head -n 1)
key=$(gsettings get org.gnome.settings-daemon.plugins.media-keys custom-keybindings)
newnum=$(grep -oE '[0-9]+' $key |sort -rn|head -n 1)
echo $newnum

grep takes the $key as filename, but I want it to search the text stored in the variable $text.

Answer 1

You can use herestring <<< to pass the string to grep:

newnum=$(grep -oE '[0-9]+' <<< "$key" | sort -rn | head -n 1)

That would be more efficient than echo "$key" | grep which would create an extra process.

Remember to enclose your variables in double quotes to prevent word splitting and globbing. See this as well.