mirror of
https://github.com/python/cpython.git
synced 2024-12-12 03:04:15 +08:00
78 lines
3.1 KiB
TeX
78 lines
3.1 KiB
TeX
\section{Standard Module \sectcode{os}}
|
|
|
|
\stmodindex{os}
|
|
This module provides a more portable way of using operating system
|
|
(OS) dependent functionality than importing an OS dependent built-in
|
|
module like \code{posix}.
|
|
|
|
When the optional built-in module \code{posix} is available, this
|
|
module exports the same functions and data as \code{posix}; otherwise,
|
|
it searches for an OS dependent built-in module like \code{mac} and
|
|
exports the same functions and data as found there. The design of all
|
|
Python's built-in OS dependen modules is such that as long as the same
|
|
functionality is available, it uses the same interface; e.g., the
|
|
function \code{os.stat(\var{file})} returns stat info about a \var{file} in a
|
|
format compatible with the POSIX interface.
|
|
|
|
Extensions peculiar to a particular OS are also available through the
|
|
\code{os} module, but using them is of course a threat to portability!
|
|
|
|
Note that after the first time \code{os} is imported, there is \emph{no}
|
|
performance penalty in using functions from \code{os} instead of
|
|
directly from the OS dependent built-in module, so there should be
|
|
\emph{no} reason not to use \code{os}!
|
|
|
|
In addition to whatever the correct OS dependent module exports, the
|
|
following variables and functions are always exported by \code{os}:
|
|
|
|
\renewcommand{\indexsubitem}{(in module os)}
|
|
\begin{datadesc}{name}
|
|
The name of the OS dependent module imported, e.g. \code{'posix'} or
|
|
\code{'mac'}.
|
|
\end{datadesc}
|
|
|
|
\begin{datadesc}{path}
|
|
The corresponding OS dependent standard module for pathname
|
|
operations, e.g., \code{posixpath} or \code{macpath}. Thus, (given
|
|
the proper imports), \code{os.path.split(\var{file})} is equivalent to but
|
|
more portable than \code{posixpath.split(\var{file})}.
|
|
\end{datadesc}
|
|
|
|
\begin{datadesc}{curdir}
|
|
The constant string used by the OS to refer to the current directory,
|
|
e.g. \code{'.'} for POSIX or \code{':'} for the Mac.
|
|
\end{datadesc}
|
|
|
|
\begin{datadesc}{pardir}
|
|
The constant string used by the OS to refer to the parent directory,
|
|
e.g. \code{'..'} for POSIX or \code{'::'} for the Mac.
|
|
\end{datadesc}
|
|
|
|
\begin{datadesc}{sep}
|
|
The character used by the OS to separate pathname components, e.g.
|
|
\code{'/'} for POSIX or \code{':'} for the Mac. Note that knowing this
|
|
is not sufficient to be able to parse or concatenate pathnames---better
|
|
use \code{os.path.split()} and \code{os.path.join()}---but it is
|
|
occasionally useful.
|
|
\end{datadesc}
|
|
|
|
\begin{funcdesc}{execl}{path\, arg0\, arg1\, ...}
|
|
This is equivalent to a call to \code{os.execv} with an \var{argv}
|
|
of \code{[\var{arg0}, \var{arg1}, ...]}.
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{execle}{path\, arg0\, arg1\, ...\, env}
|
|
This is equivalent to a call to \code{os.execve} with an \var{argv}
|
|
of \code{[\var{arg0}, \var{arg1}, ...]}.
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{execlp}{path\, arg0\, arg1\, ...}
|
|
This is like \code{execl} but duplicates the shell's actions in
|
|
searching for an executable file in a list of directories. The
|
|
directory list is obtained from \code{environ['PATH']}.
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{execvp}{path\, arg0\, arg1\, ...}
|
|
\code{execvp} is for \code{execv} what \code{execlp} is for \code{execl}.
|
|
\end{funcdesc}
|