This has come up with a few roguelike games I've downloaded recently. Trying to run the executable in the folder gets me this response:
./ia: error while loading shared libraries: libmodplug.so.1: cannot open shared object file: No such file or directory
Now, when checking in Synaptic, I definitely have libmodplug1 and libmodplug1-dev.
My guess is that the just isn't looking for the library in the same place that my installation of Ubuntu is keeping it? Even though the game sites claim that this is for Ubuntu and Linux.
I'm wondering if there's a way to fix this by perhaps symlinking a library so that the game goes where it goes to look for it but still finds what it needs?
Or is the alternative to compile it on my machine and let the library associations happen that way? (Assuming that's possible?)
(This one was for the rougelike called Infra Arcana. I'm getting the same thing from Cataclysm DDA Tiles version. I tried the game ADOM and was getting another no such file response for a different library, again one that it looks like I've got based on my Synaptic searches)
My TL;DR: is it common for programs you don't compile yourself or find through repos to not look in the right place for it's libraries? And is the only real solution to compile it yourself?
I presumed because I could see libmodplug in my installed files through synaptic, that libmodplug.so.1 was also available. Looking into it, there was a broken symlink where the file should have been.
I reinstalled libmodplug and that fixed the file. The programs depending on that library are now all working!
Posting this as an answer instead of editing the original post so as to hopefully educate the next person who assumes the same as I did! Always double-check the libraries!