cpython/Doc/library/netrc.rst

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:mod:`netrc` --- netrc file processing
======================================
.. module:: netrc
:synopsis: Loading of .netrc files.
.. moduleauthor:: Eric S. Raymond <esr@snark.thyrsus.com>
.. sectionauthor:: Eric S. Raymond <esr@snark.thyrsus.com>
**Source code:** :source:`Lib/netrc.py`
--------------
The :class:`~netrc.netrc` class parses and encapsulates the netrc file format used by
the Unix :program:`ftp` program and other FTP clients.
.. class:: netrc([file])
A :class:`~netrc.netrc` instance or subclass instance encapsulates data from a netrc
file. The initialization argument, if present, specifies the file to parse. If
no argument is given, the file :file:`.netrc` in the user's home directory --
as determined by :func:`os.path.expanduser` -- will be read. Otherwise,
a :exc:`FileNotFoundError` exception will be raised.
Parse errors will raise :exc:`NetrcParseError` with diagnostic
information including the file name, line number, and terminating token.
If no argument is specified on a POSIX system, the presence of passwords in
the :file:`.netrc` file will raise a :exc:`NetrcParseError` if the file
ownership or permissions are insecure (owned by a user other than the user
running the process, or accessible for read or write by any other user).
This implements security behavior equivalent to that of ftp and other
programs that use :file:`.netrc`.
.. versionchanged:: 3.4 Added the POSIX permission check.
.. versionchanged:: 3.7
:func:`os.path.expanduser` is used to find the location of the
:file:`.netrc` file when *file* is not passed as argument.
.. exception:: NetrcParseError
Exception raised by the :class:`~netrc.netrc` class when syntactical errors are
encountered in source text. Instances of this exception provide three
interesting attributes: :attr:`msg` is a textual explanation of the error,
:attr:`filename` is the name of the source file, and :attr:`lineno` gives the
line number on which the error was found.
.. _netrc-objects:
netrc Objects
-------------
A :class:`~netrc.netrc` instance has the following methods:
.. method:: netrc.authenticators(host)
Return a 3-tuple ``(login, account, password)`` of authenticators for *host*.
If the netrc file did not contain an entry for the given host, return the tuple
associated with the 'default' entry. If neither matching host nor default entry
is available, return ``None``.
.. method:: netrc.__repr__()
Dump the class data as a string in the format of a netrc file. (This discards
comments and may reorder the entries.)
Instances of :class:`~netrc.netrc` have public instance variables:
.. attribute:: netrc.hosts
Dictionary mapping host names to ``(login, account, password)`` tuples. The
'default' entry, if any, is represented as a pseudo-host by that name.
.. attribute:: netrc.macros
Dictionary mapping macro names to string lists.
.. note::
Passwords are limited to a subset of the ASCII character set. All ASCII
punctuation is allowed in passwords, however, note that whitespace and
non-printable characters are not allowed in passwords. This is a limitation
of the way the .netrc file is parsed and may be removed in the future.