.. _download:
Download the Native Client SDK
==============================
This page provides an overview of the Native Client SDK, and instructions for
downloading and installing the SDK.
.. raw:: html
.. _sdk-overview:
Overview
--------
The Native Client SDK includes:
- **Support for multiple Pepper versions** to compile for specific minimum
versions of Chrome.
- **Update utility** to download new bundles and updates to existing bundles.
- **Toolchains** to compile for Portable Native Client (PNaCl), traditional
Native Client (NaCl), and for compiling architecture-specific Native Client
applications with glibc.
- **Examples** Including C or C++ source files and header files illustrating
how to use NaCl and Pepper, and Makefiles to build the example with each of
the toolchains.
- **Tools** for validating Native Client modules and running modules from the
command line.
Follow the steps below to download and install the Native Client SDK.
.. _prerequisites:
Prerequisites
-------------
.. _python26-27:
Python 2.7
^^^^^^^^^^^^^^^^^
Make sure that the Python executable is in your ``PATH`` variable. Python 3.x is
not yet supported.
* On Mac and Linux, Python is likely preinstalled. Run the command ``python -V``
in a terminal window, and make sure that the version you have is 2.6.x or
2.7.x.
* On Windows, you may need to install Python. Go to `http://www.python.org/
download/ `_ and select the latest 2.x
version. In addition, be sure to add the Python directory (for example,
``C:\python27``) to the ``PATH`` `environment variable `_. Run ``python -V`` from a command line to
verify that you properly configured the PATH variable.
.. _make:
Make
^^^^
* On the Mac, you need to install ``make`` on your system before you can build
and run the examples in the SDK. One easy way to get ``make``, along with
several other useful tools, is to install `Xcode Developer Tools
`_. After installing Xcode,
go to the XCode menu, open the Preferences dialog box then select Downloads
and Components. Verify that Command Line Tools are installed. If you'd rather
not install Xcode, you can download and build an `open source version
`_ of ``make``.
To build the program you may also need to download and install `gcc
`_.
* On Windows, the Native Client SDK includes a copy of GNU Make.
.. _versioning:
Versioning
----------
Chrome is released on a six week cycle, and developer versions of Chrome are
pushed to the public beta channel three weeks before each release. As with any
software, each release of Chrome may include changes to Native Client and the
Pepper interfaces that may require modification to existing applications.
However, modules compiled for one version of Pepper/Chrome should work with
subsequent versions of Pepper/Chrome. The SDK includes multiple versions of the
Pepper APIs to help developers make adjustments to API changes and take
advantage of new features: `stable `_, `beta
`_ and `dev `_.
.. _installing-the-sdk:
Installing the SDK
------------------
.. _downloading-and-unzipping:
Downloading and Unzipping
^^^^^^^^^^^^^^^^^^^^^^^^^
#. Download the `SDK update zip file
`_.
#. Unzip the file:
* On Mac/Linux, run the command ``unzip nacl_sdk.zip`` in a terminal
window.
* On Windows, right-click on the .zip file and select "Extract All...". A
dialog box opens; enter a location and click "Extract".
A directory is created called ``nacl_sdk`` with the following files and
directories:
* ``naclsdk`` (and ``naclsdk.bat`` for Windows) --- the update utility,
which is the command you run to download and update bundles.
* ``sdk_cache`` --- a directory with a manifest file that lists the bundles
you have already downloaded.
* ``sdk_tools`` --- the code run by the ``naclsdk`` command.
.. _installing-the-stable-bundle:
Installing the stable bundle
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
#. To see the SDK bundles that are available for download, go to the
``nacl_sdk`` directory and run ``naclsdk`` with the ``list`` command. The SDK
includes a separate bundle for each version of Chrome/Pepper.
On Mac/Linux::
$ cd nacl_sdk
$ ./naclsdk list
On Windows::
> cd nacl_sdk
> naclsdk list
You should see output similar to this::
Bundles:
I: installed
*: update available
I sdk_tools (stable)
vs_addin (dev)
pepper_31 (post_stable)
pepper_32 (post_stable)
pepper_33 (post_stable)
pepper_34 (post_stable)
pepper_35 (stable)
pepper_36 (beta)
pepper_37 (dev)
pepper_canary (canary)
bionic_canary (canary)
The sample output above shows that several bundles are available for
download, and that you have already installed the latest revision of the
``sdk_tools`` bundle, which was included in the zip file. You never need to
update the ``sdk_tools`` bundle. It is updated automatically (if necessary)
whenever you run ``naclsdk``.
Bundles are labeled post-stable, stable, beta, dev, or canary. These labels
usually correspond to the current versions of Chrome. We recommend that you
develop against a "stable" bundle, because such bundles can be used by all
current Chrome users. Native Client is designed to be backward-compatible.For
example, applications developed with the ``pepper_31`` bundle can run in
Chrome 31, Chrome 32, etc..
#. Run ``naclsdk`` with the ``update`` command to download recommended bundles,
including the current "stable" bundle.
On Mac/Linux::
$ ./naclsdk update
On Windows::
> naclsdk update
By default, ``naclsdk`` only downloads bundles that are recommended,
generally those that are "stable." For example, if the current "stable"
bundle is ``pepper_35``, then the ``update`` downloads that bundle. To
download the ``pepper_36`` bundle you must ask for it explicitly::
$ ./naclsdk update pepper_36
.. _updating-bundles:
Updating bundles
----------------
#. Run ``naclsdk`` with the ``list`` command. This shows you the list of available
bundles and verifies which bundles you have installed.
On Mac/Linux::
$ ./naclsdk list
On Windows::
> naclsdk list
An asterisk (*) next to a bundle indicates that there is an update available
it. For example::
Bundles:
I: installed
*: update available
I sdk_tools (stable)
vs_addin (dev)
pepper_31 (post_stable)
pepper_32 (post_stable)
pepper_33 (post_stable)
pepper_34 (post_stable)
I* pepper_35 (stable)
pepper_36 (beta)
pepper_37 (dev)
pepper_canary (canary)
bionic_canary (canary)
If you run ``naclsdk update`` now, it warns you with a message similar to
this::
WARNING: pepper_35 already exists, but has an update available. Run update
with the --force option to overwrite the existing directory. Warning: This
will overwrite any modifications you have made within this directory.
#. To download and install the new bundle, run:
On Mac/Linux::
$ ./naclsdk update --force
On Windows::
> naclsdk update --force
.. _help-with-the-naclsdk-utility:
Help with the ``naclsdk`` utility
---------------------------------
#. For more information about the ``naclsdk`` utility, run:
On Mac/Linux::
$ ./naclsdk help
On Windows::
> naclsdk help
.. _next-steps:
Next steps
----------
* Browse the `Release Notes `_ for important
information about the SDK and new bundles.
* If you're just starting with Native Client, we recommend reading the
`Technical Overview <../overview>`_ and walking through the
`Getting Started Tutorial `_.
* If you'd rather dive in, see
`Building Native Client Modules `_.