Package description {#mainpage}

The OS module provides common operating system functions that are platform independent.

Note that for most of the functions/methods on this page, arguments are not listed. You should look at the source code to determine the arguments needed.

Summary of functionality

• Finding a suitable version of python installed in the OS for compatibility reasons
• Retrieving general operating system information
• Interacting with operating system services - start, stop, restart, set boot state, etc.
• Interacting with the OS package manager (apt, yum, macports) - installing, removing, upgrading, etc.
• A simple GPG encryption/decryption library

Detailed functionality

Python version information

The following is accessible by using the PyVersion module:

import PyVersion

Determining the executable path or name of the currently running python interpreter

PyVersion.PY_EXE

Finding a suitable installed version of python to run your code

PyVersion.checkSuitablePyExe()

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Retrieving information about the OS and performing common OS-related functions

The following is accessible by using the OS module:

import OS

Determining what OS is running

OS.flavor

Determining the OS version

OS.version

Determining the kernel version

Always returns a list or tuple of 3 ints, ex. [2, 6, 45]

OS.getKernelVersion()

Determining if an OS is unix/unix-like (Linux, Darwin, etc.)

OS.isUnix()

Determine if your python script has root permissions (ran as root or using sudo)

OS.hasRootPermissions()

Run a command in the terminal

There are lots of arguments here. Refer to the code!

OS.runCMD()

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System services

The following is accessible by using the services module:

import OS.svc

These features are self-explanatory with a quick glance at the code.

Start, stop, or restart a service right now

Change whether a service starts on boot

Remove a service

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System software packages

The following is accessible by using the packages module:

import OS.pkg

OS.pkg is more complex than some modules. Most of this is due to differences between the underlying package managers supported by OS.pkg, including:

• yum for CentOS and Red Hat is supported natively through python, since yum itself is written in python
• apt for Debian, Ubuntu, etc. is supported by using the python-apt module which will be installed along with the py.OS package if your OS is apt-based
• macports for Mac OSX is supported (sadly) only by parsing command line output using the port command

The good news is that one similar API can be used to work with packages for all 3 package managers across different platforms.

The bad news is that sometimes a package will have a different name across different package managers, even though they effectively install the same thing. To work around this, you can do for example:

if OS.pkg.isYumOS():
	OS.pkg.install("yum package name here")
elif OS.pkg.isAptOS():
	OS.pkg.install("apt-get package name here")
elif OS.pkg.isPortOS():
	OS.pkg.install("macports package name here")

Also, when using install, update, isAvailable, and similar functions, there is no need to manually update the list of available packages from the internet. This is done automatically when OS.pkg is imported.

Checking if the pkg module supports your OS

OS.pkg.isSupported()

Checking if a package is installed

OS.pkg.isInstalled()

Checking if a package is available for install

OS.pkg.isAvailable()

Installing a package

See above. You can also install an iterable of packages like:

OS.pkg.install(("nano", "vim", "emacs"))

Upgrading/updating existing packages

OS.pkg.update()

Removing/uninstalling a package

OS.pkg.remove()

• On apt, an additional argument purgeConfigFiles can be specified which, when True, is identical to apt-get purge

Platform-specific functions

Updating the kernel on apt

OS.pkg.updateKernel()

Installing a 3rd party repository on yum

OS.pkg.installRepo_RPM()
OS.pkg.installRepo_allKeys()

Installing EPEL on yum

This is a convenience method for installing EPEL. The latest EPEL RPM will be fetched.

OS.pkg.installRepo_EPEL()

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GPG

The following is accessible by using the GPG module:

from OS import GPG

Import a public or private key to the local keyring

GPG.importPublicKey(filePath)
GPG.importPrivateKey(filePath)

Get a key's ID

id = GPG.getKeyID(filename)

Sign a key

GPG.signKey(id)	

Change trust level on a key

Note that this is an interactive only function and requires the user's input, due to a limitation in the gnupg command line.

GPG.markKeyTrusted(id)

Check if a key is imported

GPG.isKeyImported(id)

Encrypt a file

outputFilePath = GPG.encrypt(inputFilePath, keyID)

Decrypt a file

Note that password is only required if the private key requires a password.

outputFilePath = GPG.decrypt(inputFilePath, password)