mirror of
https://github.com/golang/go
synced 2024-11-26 20:51:23 -07:00
ab957154b6
Update version check from 1.4 to 1.9. Suggest 2.0. R=golang-dev, r, r CC=golang-dev https://golang.org/cl/5413046
481 lines
13 KiB
HTML
481 lines
13 KiB
HTML
<!-- Getting Started -->
|
|
|
|
<h2 id="introduction">Introduction</h2>
|
|
|
|
<p>Go is an open source project, distributed under a
|
|
<a href="/LICENSE">BSD-style license</a>.
|
|
This document explains how to check out the sources,
|
|
build them on your own machine, and run them.
|
|
</p>
|
|
|
|
<div class="detail">
|
|
|
|
<p>
|
|
There are two distinct ways to experiment with Go.
|
|
This document focuses on the <code>gc</code> Go
|
|
compiler and tools (<code>6g</code>, <code>8g</code> etc.).
|
|
For information on how to use <code>gccgo</code>, a more traditional
|
|
compiler using the GCC back end, see
|
|
<a href="gccgo_install.html">Setting up and using gccgo</a>.
|
|
</p>
|
|
|
|
<p>
|
|
The Go compilers support three instruction sets.
|
|
There are important differences in the quality of the compilers for the different
|
|
architectures.
|
|
</p>
|
|
|
|
<dl>
|
|
<dt>
|
|
<code>amd64</code> (a.k.a. <code>x86-64</code>); <code>6g,6l,6c,6a</code>
|
|
</dt>
|
|
<dd>
|
|
The most mature implementation. The compiler has an effective optimizer
|
|
(registerizer) and generates good code (although <code>gccgo</code>
|
|
can do noticeably better sometimes).
|
|
</dd>
|
|
<dt>
|
|
<code>386</code> (a.k.a. <code>x86</code> or <code>x86-32</code>); <code>8g,8l,8c,8a</code>
|
|
</dt>
|
|
<dd>
|
|
Comparable to the <code>amd64</code> port.
|
|
</dd>
|
|
<dt>
|
|
<code>arm</code> (a.k.a. <code>ARM</code>); <code>5g,5l,5c,5a</code>
|
|
</dt>
|
|
<dd>
|
|
Incomplete.
|
|
It only supports Linux binaries, the optimizer is incomplete,
|
|
and floating point uses the VFP unit.
|
|
However, all tests pass.
|
|
Work on the optimizer is continuing.
|
|
Tested against a Nexus One.
|
|
</dd>
|
|
</dl>
|
|
|
|
<p>
|
|
Except for things like low-level operating system interface code, the run-time
|
|
support is the same in all ports and includes a mark-and-sweep garbage collector
|
|
(a fancier one is in the works), efficient array and string slicing,
|
|
support for segmented stacks, and a strong goroutine implementation.
|
|
</p>
|
|
|
|
<p>
|
|
The compilers can target the FreeBSD, Linux, OpenBSD
|
|
and OS X (a.k.a. Darwin) operating systems.
|
|
(A port to Microsoft Windows is in progress but incomplete. See the
|
|
<a href="http://code.google.com/p/go/wiki/WindowsPort">Windows Port</a>
|
|
page for details.)
|
|
The full set of supported combinations is listed in the discussion of
|
|
<a href="#environment">environment variables</a> below.
|
|
</p>
|
|
|
|
</div>
|
|
|
|
<h2 id="ctools">Install C tools, if needed</h2>
|
|
|
|
<p>The Go tool chain is written in C.
|
|
To build it, you need these programs installed:
|
|
<ul>
|
|
<li>GCC,
|
|
<li>the standard C libraries,
|
|
<li>the parser generator Bison,
|
|
<li>GNU <tt>make</tt> (version 3.81 or later),
|
|
and
|
|
<li><tt>awk</tt>.
|
|
</ul>
|
|
</p>
|
|
|
|
<p>On OS X, they can be
|
|
installed as part of
|
|
<a href="http://developer.apple.com/TOOLS/Xcode/">Xcode</a>.
|
|
</p>
|
|
|
|
<p>On Ubuntu/Debian, use <code>sudo apt-get install bison gawk gcc libc6-dev
|
|
make</code>. If you want to build 32-bit binaries on a 64-bit system you'll
|
|
also need the <code>libc6-dev-i386</code> package.
|
|
</p>
|
|
|
|
<h2 id="mercurial">Install Mercurial, if needed</h2>
|
|
|
|
<p>
|
|
To perform the next step you must have Mercurial installed. (Check that you have an <code>hg</code> command.) This suffices to install Mercurial on most systems:
|
|
</p>
|
|
<pre>
|
|
sudo easy_install mercurial==2.0
|
|
</pre>
|
|
(On Ubuntu/Debian, you might try <code>apt-get install python-setuptools
|
|
python-dev build-essential</code> first. The Mercurial in your distribution's
|
|
package repository will most likely be old and broken.)
|
|
</p>
|
|
<p>
|
|
If that fails, try installing manually from the <a href="http://mercurial.selenic.com/wiki/Download">Mercurial Download</a> page.</p>
|
|
</p>
|
|
|
|
<p>
|
|
Mercurial versions 1.7.x and up require the configuration of
|
|
<a href="http://mercurial.selenic.com/wiki/CACertificates">Certification Authorities</a>
|
|
(CAs). Error messages of the form:
|
|
</p>
|
|
<pre>
|
|
warning: go.googlecode.com certificate with fingerprint b1:af: ... bc not verified (check hostfingerprints or web.cacerts config setting)
|
|
</pre>
|
|
<p>
|
|
when using Mercurial indicate that the CAs are missing.
|
|
Check your Mercurial version (<code>hg --version</code>) and
|
|
<a href="http://mercurial.selenic.com/wiki/CACertificates#Configuration_of_HTTPS_certificate_authorities">configure the CAs</a>
|
|
if necessary.
|
|
</p>
|
|
|
|
<h2 id="fetch">Fetch the repository</h2>
|
|
|
|
<p>
|
|
<p>Go will install to a directory named <code>go</code>.
|
|
Change to the directory that will be its parent
|
|
and make sure the <code>go</code> directory does not exist.
|
|
Then check out the repository:</p>
|
|
|
|
<pre>
|
|
$ hg clone -u release https://go.googlecode.com/hg/ go
|
|
</pre>
|
|
|
|
<h2 id="install">Install Go</h2>
|
|
|
|
<p>
|
|
To build the Go distribution, run
|
|
</p>
|
|
|
|
<pre>
|
|
$ cd go/src
|
|
$ ./all.bash
|
|
</pre>
|
|
|
|
<p>
|
|
If all goes well, it will finish by printing output like:
|
|
</p>
|
|
|
|
<pre>
|
|
ALL TESTS PASSED
|
|
|
|
---
|
|
Installed Go for linux/amd64 in /home/you/go.
|
|
Installed commands in /home/you/go/bin.
|
|
*** You need to add /home/you/go/bin to your $PATH. ***
|
|
The compiler is 6g.
|
|
</pre>
|
|
|
|
<p>
|
|
where the details on the last few lines reflect the operating system,
|
|
architecture, and root directory used during the install.
|
|
</p>
|
|
|
|
<div class="detail">
|
|
|
|
<p>For more information about ways to control the build,
|
|
see the discussion of <a href="#environment">environment variables</a> below.</p>
|
|
</div>
|
|
|
|
<h2 id="writing">Writing programs</h2>
|
|
|
|
<p>
|
|
Given a file <code>file.go</code>, compile it using
|
|
</p>
|
|
|
|
<pre>
|
|
$ 6g file.go
|
|
</pre>
|
|
|
|
<p>
|
|
<code>6g</code> is the Go compiler for <code>amd64</code>; it will write the output
|
|
in <code>file.6</code>. The ‘<code>6</code>’ identifies
|
|
files for the <code>amd64</code> architecture.
|
|
The identifier letters for <code>386</code> and <code>arm</code>
|
|
are ‘<code>8</code>’ and ‘<code>5</code>’.
|
|
That is, if you were compiling for <code>386</code>, you would use
|
|
<code>8g</code> and the output would be named <code>file.8</code>.
|
|
</p>
|
|
|
|
<p>
|
|
To link the file, use
|
|
</p>
|
|
|
|
<pre>
|
|
$ 6l file.6
|
|
</pre>
|
|
|
|
<p>
|
|
and to run it
|
|
</p>
|
|
|
|
<pre>
|
|
$ ./6.out
|
|
</pre>
|
|
|
|
<p>A complete example:
|
|
</p>
|
|
|
|
<pre>
|
|
$ cat >hello.go <<EOF
|
|
package main
|
|
|
|
import "fmt"
|
|
|
|
func main() {
|
|
fmt.Printf("hello, world\n")
|
|
}
|
|
EOF
|
|
$ 6g hello.go
|
|
$ 6l hello.6
|
|
$ ./6.out
|
|
hello, world
|
|
$
|
|
</pre>
|
|
|
|
<p>
|
|
There is no need to list <code>hello.6</code>'s package dependencies
|
|
(in this case, package <code>fmt</code>) on the <code>6l</code>
|
|
command line.
|
|
The linker learns about them by reading <code>hello.6</code>.
|
|
</p>
|
|
|
|
<div class="detail">
|
|
<p>
|
|
To build more complicated programs, you will probably
|
|
want to use a
|
|
<code>Makefile</code>.
|
|
There are examples in places like
|
|
<code>go/src/cmd/godoc/Makefile</code>
|
|
and <code>go/src/pkg/*/Makefile</code>.
|
|
The
|
|
<a href="contribute.html">document</a>
|
|
about contributing to the Go project
|
|
gives more detail about
|
|
the process of building and testing Go programs.
|
|
</p>
|
|
</div>
|
|
|
|
<h2 id="next">What's next</h2>
|
|
|
|
<p>
|
|
Start by taking <a href="http://code.google.com/p/go-tour/">A Tour of Go</a>
|
|
or reading the <a href="go_tutorial.html">Go Tutorial</a>.
|
|
</p>
|
|
|
|
<p>
|
|
Build a web application by following the <a href="codelab/wiki/">Wiki
|
|
Codelab</a>.
|
|
</p>
|
|
|
|
<p>
|
|
Read <a href="effective_go.html">Effective Go</a> to learn about writing
|
|
idiomatic Go code.
|
|
</p>
|
|
|
|
<p>
|
|
For the full story, consult Go's extensive
|
|
<a href="docs.html">documentation</a>.
|
|
</p>
|
|
|
|
<h2 id="releases">Keeping up with releases</h2>
|
|
|
|
<p>
|
|
The Go project maintains two stable tags in its Mercurial repository:
|
|
<code>release</code> and <code>weekly</code>.
|
|
The <code>weekly</code> tag is updated about once a week, and should be used by
|
|
those who want to track the project's development.
|
|
The <code>release</code> tag is given, less often, to those weekly releases
|
|
that have proven themselves to be robust.
|
|
</p>
|
|
|
|
<p>
|
|
Most Go users will want to keep their Go installation at the latest
|
|
<code>release</code> tag.
|
|
New releases are announced on the
|
|
<a href="http://groups.google.com/group/golang-announce">golang-announce</a>
|
|
mailing list.
|
|
</p>
|
|
|
|
<p>
|
|
To update an existing tree to the latest release, you can run:
|
|
</p>
|
|
|
|
<pre>
|
|
$ cd go/src
|
|
$ hg pull
|
|
$ hg update release
|
|
$ ./all.bash
|
|
</pre>
|
|
|
|
<p>
|
|
To use the <code>weekly</code> tag run <code>hg update weekly</code> instead.
|
|
</p>
|
|
|
|
<h2 id="community">Community resources</h2>
|
|
|
|
<p>
|
|
For real-time help, there may be users or developers on
|
|
<code>#go-nuts</code> on the <a href="http://freenode.net/">Freenode</a> IRC server.
|
|
</p>
|
|
|
|
<p>
|
|
The official mailing list for discussion of the Go language is
|
|
<a href="http://groups.google.com/group/golang-nuts">Go Nuts</a>.
|
|
</p>
|
|
|
|
<p>
|
|
Bugs can be reported using the <a href="http://code.google.com/p/go/issues/list">Go issue tracker</a>.
|
|
</p>
|
|
|
|
<p>
|
|
For those who wish to keep up with development,
|
|
there is another mailing list, <a href="http://groups.google.com/group/golang-checkins">golang-checkins</a>,
|
|
that receives a message summarizing each checkin to the Go repository.
|
|
</p>
|
|
|
|
<h2 id="environment">Optional environment variables</h2>
|
|
|
|
<p>
|
|
The Go compilation environment can be customized by environment variables.
|
|
<i>None are required by the build</i>, but you may wish to set them
|
|
to override the defaults.
|
|
</p>
|
|
|
|
<dl>
|
|
<dt>
|
|
<code>$GOROOT</code>
|
|
</dt>
|
|
<dd>
|
|
The root of the Go tree, often <code>$HOME/go</code>.
|
|
This defaults to the parent of the directory where <code>all.bash</code> is run.
|
|
If you choose not to set <code>$GOROOT</code>, you must
|
|
run <code>gomake</code> instead of <code>make</code> or <code>gmake</code>
|
|
when developing Go programs using the conventional makefiles.
|
|
</dd>
|
|
|
|
<dt>
|
|
<code>$GOROOT_FINAL</code>
|
|
</dt>
|
|
<dd>
|
|
The value assumed by installed binaries and scripts when
|
|
<code>$GOROOT</code> is not set.
|
|
It defaults to the value used for <code>$GOROOT</code>.
|
|
If you want to build the Go tree in one location
|
|
but move it elsewhere after the build, set
|
|
<code>$GOROOT_FINAL</code> to the eventual location.
|
|
</dd>
|
|
|
|
<dt>
|
|
<code>$GOOS</code> and <code>$GOARCH</code>
|
|
</dt>
|
|
<dd>
|
|
The name of the target operating system and compilation architecture.
|
|
These default to the values of <code>$GOHOSTOS</code> and
|
|
<code>$GOHOSTARCH</code> respectively (described below).
|
|
|
|
<p>
|
|
Choices for <code>$GOOS</code> are
|
|
<code>darwin</code> (Mac OS X 10.5 or 10.6),
|
|
<code>freebsd</code>, <code>linux</code>, <code>openbsd</code>,
|
|
and <code>windows</code> (Windows, an incomplete port).
|
|
Choices for <code>$GOARCH</code> are <code>amd64</code> (64-bit x86, the most mature port),
|
|
<code>386</code> (32-bit x86), and
|
|
<code>arm</code> (32-bit ARM, an incomplete port).
|
|
The valid combinations of <code>$GOOS</code> and <code>$GOARCH</code> are:
|
|
<table cellpadding="0">
|
|
<tr>
|
|
<th width="50"><th align="left" width="100"><code>$GOOS</code></th> <th align="left" width="100"><code>$GOARCH</code></th> <th align="left"></th>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>darwin</code></td> <td><code>386</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>darwin</code></td> <td><code>amd64</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>freebsd</code></td> <td><code>386</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>freebsd</code></td> <td><code>amd64</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>linux</code></td> <td><code>386</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>linux</code></td> <td><code>amd64</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>linux</code></td> <td><code>arm</code></td> <td><i>incomplete</i></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>openbsd</code></td> <td><code>386</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>openbsd</code></td> <td><code>amd64</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>windows</code></td> <td><code>386</code></td> <td><i>incomplete</i></td>
|
|
</tr>
|
|
</table>
|
|
</dd>
|
|
|
|
<dt>
|
|
<code>$GOHOSTOS</code> and <code>$GOHOSTARCH</code>
|
|
</dt>
|
|
<dd>
|
|
The name of the host operating system and compilation architecture.
|
|
These default to the local system's operating system and
|
|
architecture.
|
|
|
|
<p>
|
|
Valid choices are the same as for <code>$GOOS</code> and
|
|
<code>$GOARCH</code>, listed above.
|
|
The specified values must be compatible with the local system.
|
|
For example, you should not set <code>$GOHOSTARCH</code> to
|
|
<code>arm</code> on an x86 system.
|
|
</dd>
|
|
|
|
<dt>
|
|
<code>$GOBIN</code>
|
|
</dt>
|
|
<dd>
|
|
The location where binaries will be installed.
|
|
The default is <code>$GOROOT/bin</code>.
|
|
After installing, you will want to arrange to add this
|
|
directory to your <code>$PATH</code>, so you can use the tools.
|
|
</dd>
|
|
|
|
<dt>
|
|
<code>$GOARM</code> (arm, default=6)
|
|
</dt>
|
|
<dd>
|
|
The ARM architecture version the run-time libraries should target.
|
|
Setting <code>$GOARM</code> to 5 causes the linker to emit calls
|
|
to a software floating point implementation instead of using
|
|
hardware floating point support.
|
|
</dd>
|
|
</dl>
|
|
|
|
<p>
|
|
Note that <code>$GOARCH</code> and <code>$GOOS</code> identify the
|
|
<em>target</em> environment, not the environment you are running on.
|
|
In effect, you are always cross-compiling.
|
|
By architecture, we mean the kind of binaries
|
|
that the target environment can run:
|
|
an x86-64 system running a 32-bit-only operating system
|
|
must set <code>GOARCH</code> to <code>386</code>,
|
|
not <code>amd64</code>.
|
|
</p>
|
|
|
|
<p>
|
|
If you choose to override the defaults,
|
|
set these variables in your shell profile (<code>$HOME/.bashrc</code>,
|
|
<code>$HOME/.profile</code>, or equivalent). The settings might look
|
|
something like this:
|
|
</p>
|
|
|
|
<pre>
|
|
export GOROOT=$HOME/go
|
|
export GOARCH=amd64
|
|
export GOOS=linux
|
|
</pre>
|