原始文件：
find /etc -name passwd 2>&1 | tee ee.log
1. cat -n 把 e.log 的文档内容加上行号后输入 e2.log 这个文档里：
xiluhua@localhost ~/t2scripts $ cat -n e.log | tee e2.log
/etc/passwd find: `/etc/ntp/crypto': Permission denied
find: `/etc/audisp': Permission denied
find: `/etc/audit': Permission denied find: `/etc/polkit-/localauthority': Permission denied
find: `/etc/dhcp': Permission denied
/etc/pam.d/passwd
find: `/etc/lvm/backup': Permission denied
find: `/etc/lvm/cache': Permission denied
find: `/etc/lvm/archive': Permission denied
find: `/etc/cups/ssl': Permission denied
find: `/etc/pki/rsyslog': Permission denied find: `/etc/pki/CA/private': Permission denied
find: `/etc/vmware-tools/GuestProxyData/trusted': Permission denied
find: `/etc/sudoers.d': Permission denied
find: `/etc/selinux/targeted/modules/active': Permission denied
2. cat -b 把 textfile1 和 textfile2 的文档内容加上行号（空白行不加）之后将内容附加到 textfile3 文档里：
xiluhua@localhost ~/t2scripts $ cat -b e.log | tee e3.log
/etc/passwd find: `/etc/ntp/crypto': Permission denied
find: `/etc/audisp': Permission denied
find: `/etc/audit': Permission denied find: `/etc/polkit-/localauthority': Permission denied
find: `/etc/dhcp': Permission denied
/etc/pam.d/passwd
find: `/etc/lvm/backup': Permission denied
find: `/etc/lvm/cache': Permission denied
find: `/etc/lvm/archive': Permission denied
find: `/etc/cups/ssl': Permission denied
find: `/etc/pki/rsyslog': Permission denied find: `/etc/pki/CA/private': Permission denied
find: `/etc/vmware-tools/GuestProxyData/trusted': Permission denied
find: `/etc/sudoers.d': Permission denied
find: `/etc/selinux/targeted/modules/active': Permission denied
3. cat /dev/null 清空 ee.log 文档内容：
cat /dev/null > e3.log
4. chattr +i：不得任意更动文件或目录。
root@localhost /home/xiluhua/t2scripts $ chattr +i ttt.sh $ 加了 +i 之后，root权限也删不了了
root@localhost /home/xiluhua/t2scripts $ rm -rf ttt.sh
rm: cannot remove `ttt.sh': Operation not permitted
5. chgrp
root@localhost /home/xiluhua/t2scripts # touch ttt.sh
root@localhost /home/xiluhua/t2scripts # ll ttt.sh
-rw-r--r--. root root Jan : ttt.sh
root@localhost /home/xiluhua/t2scripts # chgrp xiluhua ttt.sh
root@localhost /home/xiluhua/t2scripts # ll ttt.sh
-rw-r--r--. root xiluhua Jan : ttt.sh
6. chmod
xiluhua@localhost ~/t2 $ chmod --reference=t.sh tt.sh # 以 t.sh 为原型更改 tt.sh 的权限
xiluhua@localhost ~/t2 $ ll tt.sh
-rwxrwxr-x. xiluhua xiluhua Jan : tt.sh
xiluhua@localhost ~/t2 $
7. file (1) 用于辨识文件类型。
xiluhua@localhost ~/t2scripts $ file t.sh -i # 显示 mime 类别
t.sh: text/x-shellscript; charset=us-ascii
8. file (2) 显示符号链接的文件类型
xiluhua@localhost ~ $ ln -s t2scripts/ t2 xiluhua@localhost ~ $ file -L t2
t2: directory
9. cut
xiluhua@localhost ~/t2 $ cat /etc/passwd|head -n |cut -d : -f ,-,
root:::root:/bin/bash
bin:::bin:/sbin/nologin
daemon:::daemon:/sbin/nologin
adm:::adm:/sbin/nologin
lp:::lp:/sbin/nologin
10. lsattr 用于显示文件属性，配合 chattr 命令使用
xiluhua@localhost ~/t2 $ lsattr tt.sh
----i--------e- tt.sh
11. tee
xiluhua@localhost ~/t2 $ cat f3.log | tee f4.log f5.log # 同时输出到 f4和f5 两个文件
abc
efg
12. umask (1)指定在建立文件时预设的权限掩码。
root@localhost ~ # umask root@localhost ~ # umask -S
u=rwx,g=rx,o=rx
13. umask (2)
xiluhua@localhost ~ $ umask xiluhua@localhost ~ $ umask -S
u=rwx,g=rwx,o=rx
14. which命令用于查找文件。
which指令会在环境变量$PATH设置的目录里查找符合条件的文件。
15. whereis
root@localhost ~ # whereis bash
bash: /bin/bash /usr/share/man/man1/bash..gz
16. scp (1) 本地到远程
scp install.log xiluhua@192.168.178.132:~
17. scp (2) 远程到本地
scp xiluhua@192.168.178.132:~/rmq_bk_gc.log .
18. awk 是一种处理文本文件的语言，是一个强大的文本分析工具。
19. awk (1)
xiluhua@localhost ~/t2 $ awk '{print $1,$3}' f1.log
is
you
This's test
are
20. awk (2)
xiluhua@localhost ~/t2 $ awk '{printf "%-8s %-10s\n",$1,$4}' f1.log # 格式化输出
a
like
This's
orange,apple,mongo
21. awk (3)
提取yum list结果的第三列并除重
root@vm-xiluhua /mnt # yum -q list | awk '{print $3}'| sort -u