snoyberg/conduit — comment on commit 9658672931fae19b4ba1375a39dd4220533c27c2
File: Data/Conduit/Binary.hs line 41
By snoyberg:

It's a trick ;). The function is actually coming from the system-fileio package, which uses openFile as a binary version, and has a separate openTextFile (or something like that, I never use it).