<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
  "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
  <!ENTITY % general-entities SYSTEM "../general.ent">
  %general-entities;
]>

<sect1 id="ch-system-ninja" role="wrap">
  <?dbhtml filename="ninja.html"?>

  <sect1info condition="script">
    <productname>ninja</productname>
    <productnumber>&ninja-version;</productnumber>
    <address>&ninja-url;</address>
  </sect1info>

  <title>Ninja-&ninja-version;</title>

  <indexterm zone="ch-system-ninja">
    <primary sortas="a-Ninja">Ninja</primary>
  </indexterm>

  <sect2 role="package">
    <title/>

    <para>Ninja 是一个注重速度的小型构建系统。</para>

    <segmentedlist>
      <segtitle>&buildtime;</segtitle>
      <segtitle>&diskspace;</segtitle>

      <seglistitem>
        <seg>&ninja-ch6-sbu;</seg>
        <seg>&ninja-ch6-du;</seg>
      </seglistitem>
    </segmentedlist>

  </sect2>

  <sect2 role="installation">
    <title>安装 Ninja</title>

    <!--para>When run, ninja normally runs a maximum number of processes
    in parallel.  By default this is the number of cores on the system 
    plus two.  In some cases this can overheat a CPU or run a system out
    of memory.  If run from the command line, passing a -jN parameter
    will limit the number of parallel processes, but some packages
    embed the execution of ninja and do not pass a -j parameter.</para-->
    <para>在运行时， ninja 一般尽量并行运行更多进程，
		默认情况下最大进程数是系统 CPU 核心数加 2 得到的值。
		某些情况下，这样会导致 CPU 过热，或者耗尽系统内存。
		如果使用命令行执行 ninja，可以传递 -jN 参数以限制并行进程数，
		但某些软件包内嵌了 ninja 的执行过程，且并不传递 -j 参数。</para>

    <!--para>Using the <emphasis>optional</emphasis> patch below allows a user to
    limit the number of parallel processes via an environment variable, 
	NINJAJOBS.  <command>For example</command> setting: -->

	<para>使用下面这个 <emphasis>可选的</emphasis> 补丁，
		用户即可通过一个环境变量 NINJAJOBS 限制并行进程数量。
		<command>例如</command> 设置：

     <!-- Using <command> here to make the output bold.  We really don't want
     users setting this now and experience shows that many users blindly
     copy/paste anything in a box. -->
	 <!-- 这里的 <command> 标记用于加粗。我们确实不希望用户现在就设置
		 该变量，过去的经验表明许多用户盲目地复制粘贴矩形框中的所有内容。
		 译注：这可能是全书唯一一个被翻译的注释。-->

    <screen>export NINJAJOBS=4</screen>

    会限制 ninja 使用 4 个并行进程。</para>

    <para>如果希望使用这个补丁，执行以下命令应用它：</para>

<screen><userinput remap="pre">patch -Np1 -i ../ninja-1.8.2-add_NINJAJOBS_var-1.patch</userinput></screen>

    <para>构建 Ninja：</para>

<screen><userinput remap="configure">python3 configure.py --bootstrap</userinput></screen>

    <variablelist>
      <title>构建选项的含义：</title>

      <varlistentry>
        <term><parameter>--bootstrap</parameter></term>
        <listitem>
          <para>这个参数强制 ninja 为当前系统重新构建自身。</para>
        </listitem>
      </varlistentry>

    </variablelist>

    <para>运行以下命令以测试编译结果：</para>

<screen><userinput remap="test">python3 configure.py
./ninja ninja_test
./ninja_test --gtest_filter=-SubprocessTest.SetWithLots</userinput></screen>

    <para>安装该软件包：</para>

<screen><userinput remap="install">install -vm755 ninja /usr/bin/
install -vDm644 misc/bash-completion /usr/share/bash-completion/completions/ninja
install -vDm644 misc/zsh-completion  /usr/share/zsh/site-functions/_ninja</userinput></screen>

  </sect2>

  <sect2 id="contents-ninja" role="content">
    <title>Ninja 的内容</title>

    <segmentedlist>
      <segtitle>安装的程序</segtitle>

      <seglistitem>
        <seg>ninja</seg>
      </seglistitem>
    </segmentedlist>
    <variablelist>
      <bridgehead renderas="sect3">简要描述</bridgehead>
      <?dbfo list-presentation="list"?>
      <?dbhtml list-presentation="table"?>

      <varlistentry id="ninja">
        <term><command>ninja</command></term>
        <listitem>
          <para>是 ninja 构建系统</para>
          <indexterm zone="ch-system-ninja ninja">
            <primary sortas="b-ninja">ninja</primary>
          </indexterm>
        </listitem>
      </varlistentry>

    </variablelist>

  </sect2>

</sect1>

