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Command to enable tap to click on touchpad in XFCE

To list input devices with name containing the word "touchpad":

sed -n 's/^.*name.*"\(.*touchpad.*\)".*$/\1/I p' /proc/bus/input/devices

Example output:

user@debian:~$ sed -n 's/^.*name.*"\(.*touchpad.*\)".*$/\1/I p' /proc/bus/input/devices 
DELL0A20:00 06CB:CE65 Touchpad
user@debian:~$ 

To strip out any colons and replace spaces with underscores:

sed -n 's/^.*name.*"\(.*touchpad.*\)".*$/\1/I p' /proc/bus/input/devices | sed 's/\s/_/g' | sed 's/://g'

Hence, to enable tap to click on an input device whose name includes the word "touchpad":

xfconf-query -c pointers -pn /`sed -ne 's/^.*name.*"\(.*touchpad.*\)".*$/\1/I p' /proc/bus/input/devices | sed -e 's/\s/_/g' -e 's/://g'`/Properties/libinput_Tapping_Enabled -t 'int' -s 1