[Python-Dev] fileno function in file objects

[Martin von Loewis]

Section 2.1.7.9 of the library reference explains that file objects
support a fileno method. Is that a mandatory operation on file-like
objects (e.g. StringIO)? If so, how should it be implemented? If not,
shouldn't the documentation declare it optional?

The same question for documented attributes: closed, mode, name,
softspace: need file-like objects to support them?

Regards,
Martin