I have a file "a" and a fifo "b". Running "cp a b" prompts "cp: overwrite
b?", but answering yes just writes the contents of "a" into the fifo. If
this is intended behaviour i think it should be documented somewhere (I
didn't find any mention in --help or man cp).
This is even more confusing if you run something like cp /foo/* /bar and
you get "cp: overwrite arbitrary_file?" and you answer yes, it should then
be safe to assume all files from /foo are now in /bar if no error messages
presented themselves, but this is not the case.