libsmpeg-0.4.so is still present in the Steam runtime and installed on my system. Are there any binaries in your steam-runtime directory? If you do steam.sh --reset does that fix things up?
I appear to have the same issue. Running steam.sh --reset did not appear to correct the issue for me. I am however opted into the Steam Beta updates, wondering if it might just affect the Beta branch.
This issue does appear to be specific to the Beta branch. I opted out and Shadow Warrior and Duke 3D both appear to be working normally.
@gdrewb-valve afaik it was recently removed from the runtime, see @scottlu’s post http://steamcommunity.com/groups/steamworks/discussions/13/648816742758652213/
OK, sounds like it's expected then.
Thanks for reporting this, and thanks John for posting in that other thread.
We'll look into this quickly and contact the developers.
Bratmon you said this prevents several games from running - do you know of others?
I don't know of any others off hand, I'm afraid.
Closing as this appears to have been resolved.
Nothing extracted yet.
In a recent update, steam seems to have removed libsmpeg-0.4.so from steam-runtime. This prevents several games, including Shadow Warrior and Duke Nukem 3D from running.