备注
如果您不喜欢使用emsdk下载二进制文件,也可以 build Emscripten from source。
小技巧
if you’d like to install emscripten using the unofficial packages instead of the officially supported emsdk, see the bottom of the page.
首先,检查下面的关于 Platform-specific notes ,然后安装必要的软件包。
Emscripten SDK (emsdk) 的核心驱动程序是 Python 脚本。 您可以通过以下方式首次获取它
# Get the emsdk repo git clone https://github.com/emscripten-core/emsdk.git # Enter that directory cd emsdk
备注
你也可以不使用Git来获取emsdk,而是在 Github 上下载它.
运行下面的 emsdk 命令可以从Github上获取最新版的工具,并设置为 active :
# Fetch the latest version of the emsdk (not needed the first time you clone) git pull # Download and install the latest SDK tools. ./emsdk install latest # Make the "latest" SDK "active" for the current user. (writes .emscripten file) ./emsdk activate latest # Activate PATH and other environment variables in the current terminal source ./emsdk_env.sh备注
On Windows, run
emsdk.bat
instead of./emsdk
, andemsdk_env.bat
instead ofsource ./emsdk_env.sh
.备注
On Windows, if you use the
activate
command, the step ofemsdk_env.bat
is optional. If you want to know more, see activate SDK version.备注
git pull
将获取标签的当前列表,但是那里可能还没有最新的标签。您可以运行./emsdk update-tags
以直接更新标签列表。
如果改变了SDK的位置(例如:使用USB带到别的计算机), 需要从新运行 ./emsdk activate latest
和 source ./emsdk_env.sh
命令。
在上面的描述中,我们要求emsdk安装并激活 latest
,这是最新的标记发行版。这通常就是您想要的。
您还可以通过指定特定版本来安装它,例如,
./emsdk install 1.38.45
备注
When installing old versions from before the build infrastructure
rewrite (anything before 1.38.33
), you need to write something like
./emsdk install sdk-1.38.20-64bit
(add sdk-
and -64bit
) as that
was the naming convention at the time.
There are also “tip-of-tree builds”, which are the very latest code that passes
integration tests on Chromium CI. This is updated much more
frequently than tagged releases, but may be less stable (we tag releases
manually
using a more careful procedure). Tip-of-tree builds may be useful for continuous
integration that uses the emsdk (as Emscripten’s GitHub CI does), and you may
want to use it in your own CI as well, so that if you find a regression on your
project you can report it and prevent it from reaching a tagged release.
Tip-of-builds may also be useful if you want to test a feature that just landed
but didn’t reach a release yet. To use a tip-of-tree build, use the tot
target, and note that you must specify the backend explicitly,
# Get a tip-of-tree ./emsdk install tot
(In the above examples we installed the various targets; remember to also
activate
them as in the full example from earlier.)
Install Python 3.6 or newer (older versions may not work due to a GitHub change with SSL).
备注
Instead of running emscripten on Windows directly, you can use the Windows Subsystem for Linux to run it in a Linux environment.
备注
Emscripten requires macOS 10.14 Mojave or above.
If you use the Emscripten SDK it includes a bundled version of Python 3. Otherwise you will need to manually install and use Python 3.6 or newer.
These instructions explain how to install all the required tools. You can test whether some of these are already installed on the platform and skip those steps.
Install the Xcode Command Line Tools. These are a precondition for git.
Install Xcode from the macOS App Store.
In Xcode | Preferences | Downloads, install Command Line Tools.
Install git:
Install Xcode and the Xcode Command Line Tools (should already have been done). This will provide git to the system PATH (see this stackoverflow post).
Download and install git directly from http://git-scm.com/.
Install cmake if you do not have it yet:
Download and install latest CMake from Kitware CMake downloads.
备注
Emsdk does not install any tools to the system, or otherwise interact with Linux package managers. All file changes are done inside the emsdk/ directory.
Python is not provided by emsdk. The user is expected to install this beforehand with the system package manager:
# Install Python
sudo apt-get install python3
# Install CMake (optional, only needed for tests and building Binaryen or LLVM)
sudo apt-get install cmake
备注
If you want to use your system’s Node.js instead of the emsdk’s, it may be node
instead of nodejs
, and you can adjust the NODE_JS
attribute of your .emscripten
file to point to it.
Git is not installed automatically. Git is only needed if you want to use tools from a development branch.
# Install git
sudo apt-get install git
The easiest way to verify the installation is to compile some code using Emscripten.
You can jump ahead to the Emscripten教程, but if you have any problems building you should run through the basic tests and troubleshooting instructions in 验证Emscripten开发环境.
小技巧
You only need to install the SDK once! After that you can update to the latest SDK at any time using Emscripten SDK (emsdk).
Type the following in a command prompt
# Fetch the latest registry of available tools.
./emsdk update
# Download and install the latest SDK tools.
./emsdk install latest
# Set up the compiler configuration to point to the "latest" SDK.
./emsdk activate latest
# Activate PATH and other environment variables in the current terminal
source ./emsdk_env.sh
The package manager can do many other maintenance tasks ranging from fetching specific old versions of the SDK through to using the versions of the tools on GitHub (or even your own fork). Check out all the possibilities in the “How to” guides.
If you want to remove the whole SDK, just delete the directory containing the SDK.
It is also possible to remove specific tools in the SDK using emsdk.
The entire Emscripten SDK is also available in the form of a docker image. For example:
docker run --rm -v $(pwd):/src -u $(id -u):$(id -g) \
emscripten/emsdk emcc helloworld.cpp -o helloworld.js
See the Docker Hub page for more details and examples.
备注
The emsdk is the only officially supported way to use Emscripten that is supported by the Emscripten project, and the only one that we constantly test (emsdk CI, Emscripten GitHub CI, Chromium CI).
While we don’t officially support other ways of getting Emscripten, we definitely appreciate the efforts by third parties to package Emscripten for users’ convenience, and we’d like to help out, please get in touch if you are such a packager!
The following is a partial list of such unofficial emscripten packages:
package info: emscripten in chocolatey
maintainer: @aminya
package info: https://formulae.brew.sh/formula/emscripten
maintainer: @chenrui333
package info: https://github.com/archlinux/svntogit-community/tree/packages/emscripten/trunk
maintainer: Sven-Hendrik Haase <svenstaro@gmail.com>