How to restore $? AND $_ ?

[Sebastian Gniazdowski <sgniazdowski@xxxxxxxxx>]

Hello,
consider the following:

sched-fun() {
    # UND=$_
    local ret=$?

    sched +1 "sched-fun \$_"

    # : $UND
    return $ret
}

The point is that the 2 commented lines must be run in the same place
as the next lines after them in order to work. No way out of this
problem? It is about not disrupting user session with background
tasks, I think that this is in general important.
-- 
Sebastian Gniazdowski
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