Voici comment faire:

syndaemon -t -k -i 2 -d

-i 2
sets the idle time to 2 seconds. The idle time specifies how many seconds to wait after the last key-press before enabling the touchpad again.

-t
tells the daemon not to disable mouse movement when typing and only disable tapping and scrolling.

-k
tells the daemon to ignore modifier keys when monitoring keyboard activity (ie: allows ctrl+left click).

-d
starts as a daemon, in the background.