[homarp]

regarding your comment:

>// Probably plus means a locked door, and single quote means unlocked, or the other way around.

http://angband.oook.cz/stuff/manual.txt gives

' An open /broken door

+ A closed door

$ Gold or gems

A Angelic being

~ Light sources, Tools, Chests, Junk, Sticks, Skeletons, etc

[codetrotter]

Nice, thanks. I've updated the comments with the information you provided here :)