Handbook:Parts/Installation/Stage/zh-cn

设置日期和时间
在安装Gentoo之前，确保日期和时间正确设置. 一个错误配置的时钟可能在未来导致奇怪的结果！

要验证当前的日期和时间，运行：

如果这个日期/时间显示错误，使用 语法（月、日、时、分和年）更新它. 在这个阶段，建议使用UTC时间. 在安装的后期，将会定义时区.

比如，设置时间到2014年3月29日的16:21：

multilib（32和64位）
选择一个基础压缩包的系统可以在稍后的安装过程节省大量的时间，特别是当它是一次 choose a system profile. 一个stage包的选择将直接影响未来的系统配置，可以在以后省的头痛. 该压缩包multilib尽可能使用64位的库，只必要时对32位版本兼容. 这对于大多数安装一个很好的选择，因为它在未来的定制提供了极大的灵活性量. 那些谁希望自己的系统，能够容易地切换配置,应该下载根据各自的处理器架构multilib的压缩包选项.

大多数用户应该不需要使用“高级”tar包选项；它们用于特定的软件或硬件配置.

no-multilib（纯64位）
Selecting a no-multilib tarball to be the base of the system provides a complete 64-bit operating system environment. This effectively renders the ability to switch to multilib profiles improbable (although not impossible). Those who are just starting out with Gentoo should not choose a no-multilib tarball unless it is absolutely necessary. There should be good reasons for this decision and a responsible choice should be made.

下载阶段tar包
前往挂载根文件系统的Gentoo挂载点（很像）：

根据不同的安装媒介，这里有一堆工具可用来下载一个阶段. 这些工具之一就是，一个非图形化、目录驱动的浏览器. 要下载一个阶段，访问到Gentoo镜像列表形如：

要为使用一个HTTP代理，在URL上传入一个 选项：

之外还有一个浏览器. 像是它是一个非图形化浏览器，但不是目录驱动.

如果需要定义一个代理，设置 http_proxy 和/或 ftp_proxy 变量：

On the mirror list, select a mirror close by. Usually HTTP mirrors suffice, but other protocols are available as well. Move to the directory. There all available stage files are displayed (they might be stored within subdirectories named after the individual sub-architectures). Select one and press to download.

还有些像是最小化安装CD的附加下载：


 * A file that contains a list of all files inside the stage tarball
 * A file that contains checksums of the stage file, in different algorithms
 * A file that, like the  file, contains checksums of the stage file in different algorithms, but is also cryptographically signed to ensure it is provided by the Gentoo project

完成以后，按退出这个浏览器.

After downloading the stage file, it is possible to verify the integrity of the downloaded stage tarball. Use and compare the output with the checksums provided by the  or  file.

比如，要验证SHA512校验值：

使用命令的另外一种方式：

要验证Whirlpool校验值：

Compare the output of these commands with the value registered in the files. The values need to match, otherwise the downloaded file might be corrupt (or the digests file is).

Just like with the ISO file, it is also possible to verify the cryptographic signature of the file using  to make sure the checksums have not been tampered with:

解开阶段tar包
Now unpack the downloaded stage onto the system. We use to proceed:

Make sure that the same options ( and  ) are used. The  stands for Extract, the   for Verbose to see what happens during the extraction process (optional), the   for Decompress with bzip2, the  for Preserve permissions and the   to denote that we want to extract a File, not standard input. Finally, the  is to include the extended attributes stored in the archive as well.

Now that the stage is installed, continue with Configuring the compile options.

介绍
To optimize Gentoo, it is possible to set a couple of variables which impacts the behavior of Portage, Gentoo's officially supported package manager. All those variables can be set as environment variables (using ) but that isn't permanent. To keep the settings, Portage reads in the file, a configuration file for Portage.

Fire up an editor (in this guide we use ) to alter the optimization variables we will discuss hereafter.

From the file it is obvious how the file should be structured: commented lines start with "#", other lines define variables using the VARIABLE="content" syntax. Several of those variables are discussed next.

CFLAGS和CXXFLAGS
The CFLAGS and CXXFLAGS variables define the optimization flags for the GCC C and C++ compiler respectively. Although those are defined generally here, for maximum performance one would need to optimize these flags for each program separately. The reason for this is because every program is different. However, this is not manageable, hence the definition of these flags in the file.

In one should define the optimization flags that will make the system the most responsive generally. Don't place experimental settings in this variable; too much optimization can make programs behave bad (crash, or even worse, malfunction).

We will not explain all possible optimization options. To understand them all, read the GNU Online Manual(s) or the gcc info page ( - only works on a working Linux system). The file itself also contains lots of examples and information; don't forget to read it too.

A first setting is the  or   flag, which specifies the name of the target architecture. Possible options are described in the file (as comments). A commonly used value is native as that tells the compiler to select the target architecture of the current system (the one users are installing Gentoo on).

A second one is the  flag (that is a capital O, not a zero), which specifies the gcc optimization class flag. Possible classes are s (for size-optimized), 0 (zero - for no optimizations), 1, 2 or even 3 for more speed-optimization flags (every class has the same flags as the one before, plus some extras). is the recommended default. is known to cause problems when used system-wide, so we recommend to stick to.

Another popular optimization flag is  (use pipes rather than temporary files for communication between the various stages of compilation). It has no impact on the generated code, but uses more memory. On systems with low memory, gcc might get killed. In that case, do not use this flag.

Using  (which doesn't keep the frame pointer in a register for functions that don't need one) might have serious repercussions on the debugging of applications.

When the CFLAGS and CXXFLAGS variables are defined, combine the several optimization flags in one string. The default values contained in the stage3 archive that is unpacked should be good enough. The following one is just an example:

MAKEOPTS
The MAKEOPTS variable defines how many parallel compilations should occur when installing a package. A good choice is the number of CPUs (or CPU cores) in the system plus one, but this guideline isn't always perfect.

就位，预备，出发
Update the file to match personal preference and save (nano users would hit +).

Then continue with Installing the Gentoo base system.