fails:IO#eof? returns true on an empty stream that has just been opened
fails:IO#eof? raises IOError on stream not opened for reading
fails:IO#eof? returns false when not at end of file
fails:IO#eof? returns true after reading with read with no parameters
fails:IO#eof? returns true after reading with read
fails:IO#eof? returns true after reading with sysread
fails:IO#eof? returns true after reading with readlines
fails:IO#eof? returns false on just opened non-empty stream
fails:IO#eof? does not consume the data from the stream
fails:IO#eof? raises IOError on closed stream
fails:IO#eof? raises IOError on stream closed for reading by close_read
fails:IO#eof? returns true on one-byte stream after single-byte read
fails:IO#eof? returns true on receiving side of Pipe when writing side is closed
fails:IO#eof? returns false on receiving side of Pipe when writing side wrote some data
