Handbook:Parts/Installation/Stage/ja

日時を設定する
Gentooをインストールする前に、日付と時刻が正しく設定されているか確認しましょう. 正しく設定されていないと、後々おかしな結果になるかもしれません！

現在の日付と時刻を確認するために、を実行してください：

表示された日時が間違っていたら、 （月(MM)、日(DD)、時(hh)、分(mm)、年(YYYY)）という形式で日時を更新してください. この段階では、UTC時刻で設定することを推奨します. インストール中に、後でタイムゾーンを設定します.

例えば、 2014年の3月29日、16時21分に設定するには:

stage tarball をダウンロードする
ルートファイルシステムがマウントされている場所、Gentooのマウントポイント（おそらくでしょう）に移動してください：

インストールメディアには、stageをダウンロードするために使えるツールがいくつか含まれています. そのうちのひとつがで、グラフィカル環境を必要としないメニュー駆動型のブラウザです. stageをダウンロードするために、Gentooミラーリストへ行きましょう：

でHTTPプロキシを使うには、 オプションにプロクシのURLを渡してください:

Next to there is also the  browser. Like it is a non-graphical browser but it is not menu-driven.

If a proxy needs to be defined, export the http_proxy and/or ftp_proxy variables:

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.

Like with the minimal installation CDs, additional downloads are available:


 * 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

完了したら、を押してブラウザを終了します.

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.

例えば、SHA512チェックサムを検証するには：

コマンドを使う方法もあります：

Whirlpoolチェックサムを検証するには：

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:

stage tarball を展開する
Now unpack the downloaded stage onto the system. We use to proceed:

Make sure that the same options ( and  ) are used. The x stands for Extract, the v for Verbose to see what happens during the extraction process (optional), the j for Decompress with bzip2, the p for Preserve permissions and the f 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.

はじめに
To optimize Gentoo, it is possible to set a couple of variables which impact Portage behavior. 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 と 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.

よーい、ドン！
Update the file to match personal preference and save (nano users would hit +).

Then continue with Installing the Gentoo base system.