https://www.linuxfromscratch.org/lfs/view/11.1/chapter04/introduction.html

创建目录

在$LFS环境中创建一系列目录

[root@ecs-341537 sources]# mkdir -pv $LFS/{etc,var} $LFS/usr/{bin,lib,sbin}
mkdir: 已创建目录 "/mnt/lfs/etc"
mkdir: 已创建目录 "/mnt/lfs/var"
mkdir: 已创建目录 "/mnt/lfs/usr"
mkdir: 已创建目录 "/mnt/lfs/usr/bin"
mkdir: 已创建目录 "/mnt/lfs/usr/lib"
mkdir: 已创建目录 "/mnt/lfs/usr/sbin"

[root@ecs-341537 sources]# for i in bin lib sbin; do
>   ln -sv usr/$i $LFS/$i
> done
"/mnt/lfs/bin" -> "usr/bin"
"/mnt/lfs/lib" -> "usr/lib"
"/mnt/lfs/sbin" -> "usr/sbin"

[root@ecs-341537 sources]# case $(uname -m) in
>   x86_64) mkdir -pv $LFS/lib64 ;;
> esac
mkdir: 已创建目录 "/mnt/lfs/lib64"

查看目录结构

[root@ecs-341537 lfs]# mkdir -pv $LFS/tools
mkdir: 已创建目录 "/mnt/lfs/tools"


[root@ecs-341537 lfs]# ll
总用量 40
lrwxrwxrwx 1 root root     7 7月  23 02:17 bin -> usr/bin
drwxr-xr-x 2 root root  4096 7月  23 02:17 etc
lrwxrwxrwx 1 root root     7 7月  23 02:17 lib -> usr/lib
drwxr-xr-x 2 root root  4096 7月  23 02:17 lib64
drwx------ 2 root root 16384 7月  23 01:29 lost+found
lrwxrwxrwx 1 root root     8 7月  23 02:17 sbin -> usr/sbin
drwxrwxrwt 2 root root  4096 7月  23 02:18 sources
drwxr-xr-x 2 root root  4096 7月  23 02:20 tools
drwxr-xr-x 5 root root  4096 7月  23 02:17 usr
drwxr-xr-x 2 root root  4096 7月  23 02:17 var

创建无特权的账号

[root@ecs-341537 lfs]# groupadd lfs
[root@ecs-341537 lfs]# useradd -s /bin/bash -g lfs -m -k /dev/null lfs

-s /bin/bash　 　指定用户登入后所使用的shell。
-g lfs　指定用户所属的群组。
-m 自动建立用户的登入home目录
-k /dev/null
lfs 用户名

设置lfs用户的密码

[root@ecs-341537 lfs]# passwd lfs

设置权限

[root@ecs-341537 lfs]# chown -v lfs $LFS/{usr{,/*},lib,var,etc,bin,sbin,tools}
changed ownership of "/mnt/lfs/usr" from root to lfs
changed ownership of "/mnt/lfs/usr/bin" from root to lfs
changed ownership of "/mnt/lfs/usr/lib" from root to lfs
changed ownership of "/mnt/lfs/usr/sbin" from root to lfs
"/mnt/lfs/lib" 的所有者已保留为lfs
changed ownership of "/mnt/lfs/var" from root to lfs
changed ownership of "/mnt/lfs/etc" from root to lfs
"/mnt/lfs/bin" 的所有者已保留为lfs
"/mnt/lfs/sbin" 的所有者已保留为lfs
changed ownership of "/mnt/lfs/tools" from root to lfs
[root@ecs-341537 lfs]# case $(uname -m) in
>   x86_64) chown -v lfs $LFS/lib64 ;;
> esac
changed ownership of "/mnt/lfs/lib64" from root to lfs

[root@ecs-341537 lfs]# chown -v lfs $LFS/sources
changed ownership of "/mnt/lfs/sources" from root to lfs

接下来以lfs的身份登录

[root@ecs-341537 lfs]# su - lfs
-bash-4.2$

-bash-4.2$ whoami
lfs

设置环境

-bash-4.2$ cat > ~/.bash_profile << "EOF"
> exec env -i HOME=$HOME TERM=$TERM PS1='\u:\w\$ ' /bin/bash
> EOF

-bash-4.2$ echo $HOME
/home/lfs
-bash-4.2$ echo $TERM
xterm-256color
-bash-4.2$ echo PS1
PS1

-bash-4.2$ cat > ~/.bashrc << "EOF"
> 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
> EOF

切换到root用户

-bash-4.2$ exit
logout
[root@ecs-341537 lfs]# whoami
root

[root@ecs-341537 lfs]# [ ! -e /etc/bash.bashrc ] || mv -v /etc/bash.bashrc /etc/bash.bashrc.NOUSE

切换回lfs用户

[root@ecs-341537 etc]# su - lfs
lfs:~$ source ~/.bash_profile
lfs:~$ echo $LFS
/mnt/lfs
lfs:~$ echo $PATH
/mnt/lfs/tools/bin:/usr/bin

查看当前.bashrc

lfs:~$ ls -a
.  ..  .bash_history  .bash_profile  .bashrc

lfs:~$ cat .bashrc
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

设置多线程处理make
其实这里设置以后多半有坑，我的机器cpu和内存有限，在后面编译gcc的时候就反复遇到瓶颈。
直接用-j1可能还少点麻烦

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
MAKEFLAGS='-j4'
export LFS LC_ALL LFS_TGT PATH CONFIG_SITE MAKEFLAGS

使设置生效

lfs:~$ source .bashrc
lfs:~$ set | grep MAKEFLAGS
MAKEFLAGS=-j4