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(python2.1-lib.info)user

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User-specific configuration hook
================================

A standard way to reference user-specific modules.

As a policy, Python doesn't run user-specified code on startup of
Python programs.  (Only interactive sessions execute the script
specified in the `PYTHONSTARTUP' environment variable if it exists).

However, some programs or sites may find it convenient to allow users
to have a standard customization file, which gets run when a program
requests it.  This module implements such a mechanism.  A program that
wishes to use the mechanism must execute the statement

     import user

The `user' module looks for a file `.pythonrc.py' in the user's home
directory and if it can be opened, executes it (using `execfile()' ) in
its own (i.e. the module `user''s) global namespace.  Errors during
this phase are not caught; that's up to the program that imports the
`user' module, if it wishes.  The home directory is assumed to be named
by the `HOME' environment variable; if this is not set, the current
directory is used.

The user's `.pythonrc.py' could conceivably test for `sys.version' if
it wishes to do different things depending on the Python version.

A warning to users: be very conservative in what you place in your
`.pythonrc.py' file.  Since you don't know which programs will use it,
changing the behavior of standard modules or functions is generally not
a good idea.

A suggestion for programmers who wish to use this mechanism: a simple
way to let users specify options for your package is to have them
define variables in their `.pythonrc.py' file that you test in your
module.  For example, a module `spam' that has a verbosity level can
look for a variable `user.spam_verbose', as follows:

     import user
     try:
         verbose = user.spam_verbose  # user's verbosity preference
     except AttributeError:
         verbose = 0                  # default verbosity

Programs with extensive customization needs are better off reading a
program-specific customization file.

Programs with security or privacy concerns should _not_ import this
module; a user can easily break into a program by placing arbitrary
code in the `.pythonrc.py' file.

Modules for general use should _not_ import this module; it may
interfere with the operation of the importing program.

See also:
     Note: site Site-wide customization mechanism.