mirror of
https://github.com/python/cpython.git
synced 2025-11-04 07:31:38 +00:00
49 lines
1.8 KiB
TeX
49 lines
1.8 KiB
TeX
\section{Standard module \sectcode{commands}} % If implemented in Python
|
|
\label{module-commands}
|
|
\stmodindex{commands}
|
|
|
|
The \code{commands} module contains wrapper functions for \code{os.popen()}
|
|
which take a system command as a string and return any output generated by
|
|
the command, and optionally, the exit status.
|
|
|
|
The \code{commands} module is only usable on systems which support
|
|
\code{popen()} (currently \UNIX{}).
|
|
|
|
The \code{commands} module defines the following functions:
|
|
|
|
\renewcommand{\indexsubitem}{(in module commands)}
|
|
\begin{funcdesc}{getstatusoutput}{cmd}
|
|
Execute the string \var{cmd} in a shell with \code{os.popen()} and return
|
|
a 2-tuple (status, output). \var{cmd} is actually run as
|
|
\samp{\{\ cmd \} ; 2$>$\$1}, so that the returned output will contain output
|
|
or error messages. A trailing newline is stripped from the output.
|
|
The exit status for the command can be interpreted according to the
|
|
rules for the \C{} function \code{wait()}.
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{getoutput}{cmd}
|
|
Like \code{getstatusoutput()}, except the exit status is ignored and
|
|
the return value is a string containing the command's output.
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{getstatus}{file}
|
|
Return the output of \samp{ls -ld \var{file}} as a string. This
|
|
function uses the \code{getoutput()} function, and properly escapes
|
|
backslashes and dollar signs in the argument.
|
|
\end{funcdesc}
|
|
|
|
Example:
|
|
|
|
\begin{verbatim}
|
|
>>> import commands
|
|
>>> commands.getstatusoutput('ls /bin/ls')
|
|
(0, '/bin/ls')
|
|
>>> commands.getstatusoutput('cat /bin/junk')
|
|
(256, 'cat: /bin/junk: No such file or directory')
|
|
>>> commands.getstatusoutput('/bin/junk')
|
|
(256, 'sh: /bin/junk: not found')
|
|
>>> commands.getoutput('ls /bin/ls')
|
|
'/bin/ls'
|
|
>>> commands.getstatus('/bin/ls')
|
|
'-rwxr-xr-x 1 root 13352 Oct 14 1994 /bin/ls'
|
|
\end{verbatim}
|