There are four basic ways to create a Stdio.File object.
The first is calling it without any arguments, in which case the you
have to call Stdio.File.open, Stdio.File.connect or some other method which connects
the File object with a stream.
The second way is calling it with a filename and open mode. This is
the same thing as cloning and then calling Stdio.File.open, except shorter and
faster.
The third way is to call it with descriptorname of "stdin",
"stdout" or "stderr". This will open the specified
standard stream.
For the advanced users, you can use the file descriptors of the
systems (note: emulated by pike on some systems - like NT). This is
only useful for streaming purposes on unix systems. This is not
recommended at all if you don't know what you're into. Default
mode for this is "rw".