exception for invalid byte sequences

[Henning Thielemann]

Documentation for hGetChar et.al. [1] does not mention the exception for 
invalid byte sequences in the current encoding.

It seems it throws an exception called "invalid argument":

IO> h <- IO.openFile "/tmp/invalid" IO.ReadMode
IO> IO.hGetChar h
*** Exception: /tmp/invalid: hGetChar: invalid argument (invalid byte sequence)


https://hackage.haskell.org/package/base-4.14.0.0/docs/System-IO.html#v:hGetChar