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diff --git a/Doc/lib/libuser.tex b/Doc/lib/libuser.tex deleted file mode 100644 index 4e915a2..0000000 --- a/Doc/lib/libuser.tex +++ /dev/null @@ -1,71 +0,0 @@ -\section{\module{user} --- - User-specific configuration hook} - -\declaremodule{standard}{user} -\modulesynopsis{A standard way to reference user-specific modules.} - - -\indexii{.pythonrc.py}{file} -\indexiii{user}{configuration}{file} - -As a policy, Python doesn't run user-specified code on startup of -Python programs. (Only interactive sessions execute the script -specified in the \envvar{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 - -\begin{verbatim} -import user -\end{verbatim} - -The \module{user} module looks for a file \file{.pythonrc.py} in the user's -home directory and if it can be opened, executes it (using -\function{execfile()}\bifuncindex{execfile}) in its own (the -module \module{user}'s) global namespace. Errors during this phase -are not caught; that's up to the program that imports the -\module{user} module, if it wishes. The home directory is assumed to -be named by the \envvar{HOME} environment variable; if this is not set, -the current directory is used. - -The user's \file{.pythonrc.py} could conceivably test for -\code{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 -\file{.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 \file{.pythonrc.py} file that you test in -your module. For example, a module \module{spam} that has a verbosity -level can look for a variable \code{user.spam_verbose}, as follows: - -\begin{verbatim} -import user - -verbose = bool(getattr(user, "spam_verbose", 0)) -\end{verbatim} - -(The three-argument form of \function{getattr()} is used in case -the user has not defined \code{spam_verbose} in their -\file{.pythonrc.py} file.) - -Programs with extensive customization needs are better off reading a -program-specific customization file. - -Programs with security or privacy concerns should \emph{not} import -this module; a user can easily break into a program by placing -arbitrary code in the \file{.pythonrc.py} file. - -Modules for general use should \emph{not} import this module; it may -interfere with the operation of the importing program. - -\begin{seealso} - \seemodule{site}{Site-wide customization mechanism.} -\end{seealso} |