I'm using an Raspberry Pi in combination with Chromium (kiosk mode) to show up some stats. The Pi doesn't have an connected keyboard so I searched for a solution to send keystrokes from the terminal to the Chromium (tab) process. Normal input does work but how do I send something like F5 (special key; browser refresh) via this solution?

# pidof chromium
20809 20790 20788 20786 20783
# echo 'some text' > /proc/20809/fd/0