- {Stream}
The process.stderr property returns a stream connected to
stderr (fd 2). It is a [net.Socket][] (which is a [Duplex][]
stream) unless fd 2 refers to a file, in which case it is
a [Writable][] stream.
Note: process.stderr differs from other Node.js streams in important ways,
see [note on process I/O][] for more information.