Unistall a non-key door lock? I see a small slot, but I still can't pulling off the...

I see a small slot, but I still can't pulling off the knob when I use a small screwdriver to push surrounded by the slot. When I look at the small slot more detail, it seems a small metal inside that can be pushed. Any direction is welcome.
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Answers:    yes it is a slip know. you push contained by on the wire within the slot and then verbs or twist and verbs and it will come off. The screw for the door are under the knob, losing the cover plate.

second option is a pipe wrench and verbs is off or break it and remove the cover plate or a hack saw, I own had to use both next to older locks that enjoy rusted on.
Can I use blown contained by insulation surrounded...
f this is a commercial type knob, you have to hold a special wrench to unscrew the knob to take stale the plate that hides the screw. Then sometimes that plte screws together too.