80 lines
2.5 KiB
ReStructuredText
80 lines
2.5 KiB
ReStructuredText
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:mod:`commands` --- Utilities for running commands
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==================================================
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.. module:: commands
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:platform: Unix
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:synopsis: Utility functions for running external commands.
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:deprecated:
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.. deprecated:: 2.6
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The :mod:`commands` module has been removed in Python 3.0. Use the
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:mod:`subprocess` module instead.
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.. sectionauthor:: Sue Williams <sbw@provis.com>
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The :mod:`commands` module contains wrapper functions for :func:`os.popen` which
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take a system command as a string and return any output generated by the command
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and, optionally, the exit status.
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The :mod:`subprocess` module provides more powerful facilities for spawning new
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processes and retrieving their results. Using the :mod:`subprocess` module is
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preferable to using the :mod:`commands` module.
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.. warning::
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In 3.x, :func:`getstatus` and two undocumented functions (:func:`mk2arg` and
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:func:`mkarg`) have been removed. Also, :func:`getstatusoutput` and
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:func:`getoutput` have been moved to the :mod:`subprocess` module.
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The :mod:`commands` module defines the following functions:
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.. function:: getstatusoutput(cmd)
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Execute the string *cmd* in a shell with :func:`os.popen` and return a 2-tuple
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``(status, output)``. *cmd* is actually run as ``{ cmd ; } 2>&1``, so that the
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returned output will contain output or error messages. A trailing newline is
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stripped from the output. The exit status for the command can be interpreted
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according to the rules for the C function :cfunc:`wait`.
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.. function:: getoutput(cmd)
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Like :func:`getstatusoutput`, except the exit status is ignored and the return
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value is a string containing the command's output.
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.. function:: getstatus(file)
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Return the output of ``ls -ld file`` as a string. This function uses the
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:func:`getoutput` function, and properly escapes backslashes and dollar signs in
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the argument.
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.. deprecated:: 2.6
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This function is nonobvious and useless. The name is also misleading in the
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presence of :func:`getstatusoutput`.
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Example::
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>>> import commands
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>>> commands.getstatusoutput('ls /bin/ls')
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(0, '/bin/ls')
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>>> commands.getstatusoutput('cat /bin/junk')
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(256, 'cat: /bin/junk: No such file or directory')
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>>> commands.getstatusoutput('/bin/junk')
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(256, 'sh: /bin/junk: not found')
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>>> commands.getoutput('ls /bin/ls')
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'/bin/ls'
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>>> commands.getstatus('/bin/ls')
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'-rwxr-xr-x 1 root 13352 Oct 14 1994 /bin/ls'
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.. seealso::
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Module :mod:`subprocess`
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Module for spawning and managing subprocesses.
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