Stop stdin while command is running

How to stop stdin while command is running in ash (not bash)? For example: 1. sleep 10 1. type echo hello while sleep is still running 1. observe hello is in stdout after sleep finishes Desired: 1. sleep 10 1. type echo hello while sleep is still running 1. observe shell as if nothing was typed in while sleep was running I expect the solution would be something like: tput ; sleep 10; tput ; This will not be in a shell script (only needs to work with interactive shell).