Disable links to 404 and unpublished nodes

I programmatically create nodes and alinks for the internal structure. I found out that alinks is linking also to an unpublished node. It's not really nice if u click on an link and u see this node is not available. Is it easy to change this. I am also regarding to the schedule module. Same problem.

An idea for a solution is maybe an on / off switch with an api or checking if the internal node is published.

Thx for this module