I would like to force my screen to blank, and leave it stay blank regardless of what I do with my keyboard and mouse until it receives a command to unblank (kind of like a lock).

The commands I know are:

```
xset dpms force off
sleep 2
xset dpms force on

```

I only want it to blank for two seconds then unblank, but I want it to absolutely stay blank for these two seconds no matter what. Can this be done?