Translation Source string Target string
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
When logged on as user <systemitem class="username">lfs</systemitem>, or when switched to the &lfs-user; user using an <command>su</command> command with the <quote><parameter>-</parameter></quote> option, the initial shell is a <emphasis>login</emphasis> shell which reads the <filename>/etc/profile</filename> of the host (probably containing some settings and environment variables) and then <filename>.bash_profile</filename>. The <command>exec env -i.../bin/bash</command> command in the <filename>.bash_profile</filename> file replaces the running shell with a new one with a completely empty environment, except for the <envar>HOME</envar>, <envar>TERM</envar>, and <envar>PS1</envar> variables. This ensures that no unwanted and potentially hazardous environment variables from the host system leak into the build environment.
在以 <systemitem class="username">lfs</systemitem> 用户登录时，初始的 shell 一般是一个<emphasis>登录</emphasis> shell。它读取宿主系统的 <filename>/etc/profile</filename> 文件 (可能包含一些设置和环境变量)，然后读取 <filename>.bash_profile</filename>。我们在 <filename>.bash_profile</filename> 中使用 <command>exec env -i.../bin/bash</command> 命令，新建一个除了 <envar>HOME</envar>, <envar>TERM</envar> 以及 <envar>PS1</envar> 外没有任何环境变量的 shell，替换当前 shell，防止宿主环境中不必要和有潜在风险的环境变量进入编译环境。通过使用以上技巧，我们创建了一个干净环境。
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
The new instance of the shell is a <emphasis>non-login</emphasis> shell, which does not read, and execute, the contents of the <filename>/etc/profile</filename> or <filename>.bash_profile</filename> files, but rather reads, and executes, the <filename>.bashrc</filename> file instead. Create the <filename>.bashrc</filename> file now:
新的 shell 实例是 <emphasis>非登录</emphasis> shell，它不会读取和执行 <filename>/etc/profile</filename> 或者 <filename>.bash_profile</filename> 的内容，而是读取并执行 <filename>.bashrc</filename> 文件。现在我们就创建一个 <filename>.bashrc</filename> 文件：
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
<userinput>cat &gt; ~/.bashrc &lt;&lt; "EOF"
<literal>set +h
umask 022
LFS=/mnt/lfs
LC_ALL=POSIX
LFS_TGT=$(uname -m)-lfs-linux-gnu
PATH=/usr/bin
if [ ! -L /bin ]; then PATH=/bin:$PATH; fi
PATH=$LFS/tools/bin:$PATH
CONFIG_SITE=$LFS/usr/share/config.site
export LFS LC_ALL LFS_TGT PATH CONFIG_SITE</literal>
EOF</userinput>
<userinput>cat &gt; ~/.bashrc &lt;&lt; "EOF"
<literal>set +h
umask 022
LFS=/mnt/lfs
LC_ALL=POSIX
LFS_TGT=$(uname -m)-lfs-linux-gnu
PATH=/usr/bin
if [ ! -L /bin ]; then PATH=/bin:$PATH; fi
PATH=$LFS/tools/bin:$PATH
export LFS LC_ALL LFS_TGT PATH</literal>
EOF</userinput>
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
The <command>set +h</command> command turns off <command>bash</command>'s hash function. Hashing is ordinarily a useful feature&mdash;<command>bash</command> uses a hash table to remember the full path to executable files to avoid searching the <envar>PATH</envar> time and again to find the same executable. However, the new tools should be used as soon as they are installed. Switching off the hash function forces the shell to search the <envar>PATH</envar> whenever a program is to be run. As such, the shell will find the newly compiled tools in <filename class="directory">$LFS/tools/bin</filename> as soon as they are available without remembering a previous version of the same program provided by the host distro, in <filename class='directory'>/usr/bin</filename> or <filename class='directory'>/bin</filename>.
<command>set +h</command> 命令关闭 <command>bash</command> 的散列功能。一般情况下，散列是很有用的 —— <command>bash</command> 使用一个散列表维护各个可执行文件的完整路径，这样就不用每次都在 <envar>PATH</envar> 指定的目录中搜索可执行文件。然而，在构建 LFS 时，我们希望总是使用最新安装的工具。因此，需要关闭散列功能，使得 shell 在运行程序时总是搜索 <envar>PATH</envar>。这样，shell 总是能够找到 <filename class="directory">$LFS/tools</filename> 目录中那些最新编译的工具，而不是使用之前记忆的另一个目录中的程序。
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
Setting the user file-creation mask (umask) to 022 ensures that newly created files and directories are only writable by their owner, but are readable and executable by anyone (assuming default modes are used by the <ulink role='man' url='&man;open.2'>open(2)</ulink> system call, new files will end up with permission mode 644 and directories with mode 755).
将用户的文件创建掩码 (umask) 设定为 022，保证只有文件所有者可以写新创建的文件和目录，但任何人都可读取、执行它们。(如果 <function>open(2)</function> 系统调用使用默认模式，则新文件将具有权限码 644，而新目录具有权限码 755)。
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
The <envar>LC_ALL</envar> variable controls the localization of certain programs, making their messages follow the conventions of a specified country. Setting <envar>LC_ALL</envar> to <quote>POSIX</quote> or <quote>C</quote> (the two are equivalent) ensures that everything will work as expected in the cross-compilation environment.
<envar>LC_ALL</envar> 环境变量控制某些程序的本地化行为，使得它们以特定国家的语言和惯例输出消息。将 <envar>LC_ALL</envar> 设置为 <quote>POSIX</quote> 或者 <quote>C</quote>(这两种设置是等价的) 可以保证在 chroot 环境中所有命令的行为完全符合预期，而与宿主的本地化设置无关。
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
<parameter>LFS_TGT=$(uname -m)-lfs-linux-gnu</parameter>
<parameter>LFS_TGT=(uname -m)-lfs-linux-gnu</parameter>
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
The <envar>LFS_TGT</envar> variable sets a non-default, but compatible machine description for use when building our cross-compiler and linker and when cross-compiling our temporary toolchain. More information is provided by <xref linkend="ch-tools-toolchaintechnotes" role=""/>.
<envar>LFS_TGT</envar>变量设定了一个非默认，但与宿主系统兼容的机器描述符。该描述符被用于构建交叉编译器和交叉编译临时工具链。<xref linkend="ch-tools-toolchaintechnotes" role=""/>包含了关于这个描述符的更多信息。
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
Many modern Linux distributions have merged <filename class="directory">/bin</filename> and <filename class="directory">/usr/bin</filename>. When this is the case, the standard <envar>PATH</envar> variable should be set to <filename class="directory">/usr/bin/</filename> for the <xref linkend="chapter-temporary-tools"/> environment. When this is not the case, the following line adds <filename class="directory">/bin</filename> to the path.
许多现代 Linux 发行版合并了 <filename class="directory">/bin</filename> 和 <filename class="directory">/usr/bin</filename>。在这种情况下，标准 <envar>PATH</envar> 变量只需要被设定为 <filename class="directory">/usr/bin</filename>，即可满足<xref linkend="chapter-temporary-tools"/>的环境。否则，后续命令将会增加 <filename class="directory">/bin</filename> 到搜索路径中。
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
If <filename class="directory">/bin</filename> is not a symbolic link, it must be added to the <envar>PATH</envar> variable.
如果 <filename class="directory">/bin</filename> 不是符号链接，则它需要被添加到 <envar>PATH</envar> 变量中。
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
By putting <filename class="directory">$LFS/tools/bin</filename> ahead of the standard <envar>PATH</envar>, the cross-compiler installed at the beginning of <xref linkend="chapter-cross-tools"/> is picked up by the shell immediately after its installation. This, combined with turning off hashing, limits the risk that the compiler from the host is used instead of the cross-compiler.
我们将 <filename class="directory">$LFS/tools/bin</filename> 附加在默认的 <envar>PATH</envar> 环境变量之前，这样在<xref linkend="chapter-cross-tools"/>中，我们一旦安装了新的程序，shell 就能立刻使用它们。这与关闭散列功能相结合，降低了在第 5 章环境中新程序可用时错误地使用宿主系统中旧程序的风险。
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
<parameter>CONFIG_SITE=$LFS/usr/share/config.site</parameter>
<parameter>PATH=/usr/bin</parameter>
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
In <xref linkend="chapter-cross-tools"/> and <xref linkend="chapter-temporary-tools"/>, if this variable is not set, <command>configure</command> scripts may attempt to load configuration items specific to some distributions from <filename>/usr/share/config.site</filename> on the host system. Override it to prevent potential contamination from the host.
 
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
<parameter>export ...</parameter>
<parameter>set +h</parameter>
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
While the preceding commands have set some variables, in order to make them visible within any sub-shells, we export them.
前面的命令设定了一些变量，为了让所有子 shell 都能使用这些变量，需要导出它们。
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
Several commercial distributions add an undocumented instantiation of <filename>/etc/bash.bashrc</filename> to the initialization of <command>bash</command>. This file has the potential to modify the <systemitem class="username">lfs</systemitem> user's environment in ways that can affect the building of critical LFS packages. To make sure the <systemitem class="username">lfs</systemitem> user's environment is clean, check for the presence of <filename>/etc/bash.bashrc</filename> and, if present, move it out of the way. As the <systemitem class="username">root</systemitem> user, run:
一些商业发行版未做文档说明地将 <filename>/etc/bash.bashrc</filename> 引入 <command>bash</command> 初始化过程。该文件可能修改 <systemitem class="username">lfs</systemitem> 用户的环境，并影响 LFS 关键软件包的构建。为了保证 <systemitem class="username">lfs</systemitem> 用户环境的纯净，检查 <filename>/etc/bash.bashrc</filename> 是否存在，如果它存在就将它移走。以 <systemitem class="username">root</systemitem> 用户身份，运行：
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
When the <systemitem class="username">lfs</systemitem> user is no longer needed (at the beginning of <xref linkend="chapter-chroot-temporary-tools"/>), you may safely restore <filename>/etc/bash.bashrc</filename> (if desired).
<systemitem class="username">lfs</systemitem> 用户在<xref linkend="chapter-chroot-temporary-tools"/>一章开始后，就不再被使用，您 (如果希望的话) 可以复原 <filename>/etc/bash.bashrc</filename> 文件。
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
For many modern systems with multiple processors (or cores) the compilation time for a package can be reduced by performing a "parallel make" by telling the make program how many processors are available via a command line option or an environment variable. For instance, an Intel Core i9-13900K processor has 8 P (performance) cores and 16 E (efficiency) cores, and a P core can simultaneously run two threads so each P core are modeled as two logical cores by the Linux kernel. As the result there are 32 logical cores in total. One obvious way to use all these logical cores is allowing <command>make</command> to spawn up to 32 build jobs. This can be done by passing the <parameter>-j32</parameter> option to <command>make</command>:
 
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
<userinput>make -j32</userinput>
<userinput>source ~/.bash_profile</userinput>
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
Or set the <envar>MAKEFLAGS</envar> environment variable and its content will be automatically used by <command>make</command> as command line options:
 
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
<userinput>export MAKEFLAGS=-j32</userinput>
 
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
Never pass a <parameter>-j</parameter> option without a number to <command>make</command> or set such an option in <envar>MAKEFLAGS</envar>. Doing so will allow <command>make</command> to spawn infinite build jobs and cause system stability problems.
 
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
To use all logical cores available for building packages in <xref linkend='chapter-cross-tools'/> and <xref linkend='chapter-temporary-tools'/>, set <envar>MAKEFLAGS</envar> now in <filename>.bashrc</filename>:
 
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
<userinput>cat &gt;&gt; ~/.bashrc &lt;&lt; "EOF"
<literal>export MAKEFLAGS=-j<replaceable>$(nproc)</replaceable></literal>
EOF</userinput>
<userinput>cat &gt; ~/.bash_profile &lt;&lt; "EOF"
<literal>exec env -i HOME=$HOME TERM=$TERM PS1='\u:\w\$ ' /bin/bash</literal>
EOF</userinput>
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
Replace <replaceable>$(nproc)</replaceable> with the number of logical cores you want to use if you don't want to use all the logical cores.
 
Linux From Scratch/chapter04_settingenviron — Chinese (Simplified Han script)
Finally, to ensure the environment is fully prepared for building the temporary tools, force the <command>bash</command> shell to read the new user profile:
最后，为了完全准备好编译临时工具的环境，指示 shell 读取刚才创建的配置文件：