Devops系列：Centos7 快捷键、目录结构、用户目录

一.快捷键

1.历史命令

查看历史命令:history

[root@centos-master ~]# history 
    1  2020-10-25 21:03:39  
    2  2020-09-17 20:43:52 ls1  2020-10-25 21:03:39  
    2  2020-09-17 20:43:52 ls
    3  2020-09-17 20:43:54 ls
    4  2020-09-17 20:43:57 cd /
    5  2020-09-17 20:43:58 ls
    6  2020-09-17 20:50:31 cd /
    7  2020-09-17 20:50:33 ls

向上遍历:ctrl+p  方向键向上

向下遍历:ctrl+n  方向键向下

2.光标移动

光标向前移动:ctrl+b 方向键向左

光标向后移动:ctrl+f 方向键向右

光标移动到行首:ctrl+a 

光标移动到行尾:ctrl+e

删除光标前面的一个字符:ctrl+h 退格键

删除光标后面的一个字符:ctrl+d 

删除光标前面的字符:ctrl+u

3.清屏

清屏:ctrl+l  clear 

二.目录结构

 

 /bin:存储基本命令的目录

 

 /boot:开机启动项文件，包括一些连接文件和镜像文件

 

 /dev:(device)设备目录,该目录下存放的是linux的外部设备,在linux中访问设备和访问文件是一样的

 

 /etc:存放所有的系统管理所需要的配置文件和子目录

 

/home:用户的主目录,在linux中每个用户都有一个自己的目录,一般该目录是以用户的账号命名的

 

 /lib:存放着系统最基本的动态连接共享库,类似于windows中的dll文件

 

/lost+found:一般情况下是空的,当系统非法关机后就存放了一些文件

/media:linux会自动识别一些设备,例如U盘、光驱等,linux会把这些设备挂载在目录中(自动挂载)

/mnt:手动挂载目录 

/opt:主机额外安装软件摆放的位置,第三方软件

/proc:虚拟目录,他是系统内存的映射,我们可以通过这个目录来获取系统信息,这个目录不在硬盘上而是在内存里,比如说可以通过下面命令来屏蔽主机的ping命令,使别人无法ping你的机器

[root@centos-master ~]# echo 1 > /proc/sys/net/ipv4/icmp_echo_ignore_all 

 

/root:系统管理员目录,超级权限者的用户主目录

/sbin:super user的意思,存放的系统管理员使用的系统管理程序

/srv:存放着一些服务启动后需要提取的数据

/tmp:存放一些临时文件的目录

/usr:用户很多程序和文件都放在这个目录,类似于windows中的program files目录

/usr/bin:系统用户使用的应用程序

/usr/sbin:超级用户使用的比较高级的管理程序和系统守护程序

/usr/src:内核源代码默认放置的目录

/var:存放着不断扩展的东西,习惯将经常修改的文件放在这个目录下,包括各种日志文件

三.用户目录

1.绝对路径: cd /usr/src

2.相对路径: cd usr/src

3.当前路径: cd . 

4.当前路径的上一级: cd ..

5.邻近的两个路径相互切换:cd  -

[root@centos-master ~]# cd /
[root@centos-master /]# ls
bin  boot  data  dev  etc  home  lib  lib64  lost+found  media  mnt  opt  proc  root  run  sbin  srv  sys  tmp  usr  var
[root@centos-master /]# cd etc/
[root@centos-master etc]# ls
abrt                     cron.d                   environment  gshadow-          krb5.conf                 man_db.conf           pam.d           rc3.d           sestatus.conf   systemd
acpi                     cron.daily               ethertypes   gss               krb5.conf.d               maven                 passwd          rc4.d           setuptool.d     system-release
adjtime                  cron.deny                exports      host.conf         ld.so.cache               mke2fs.conf           passwd-         rc5.d           shadow          system-release-cpe
aliases                  cron.hourly              favicon.png  hostname          ld.so.conf                modprobe.d            pkcs11          rc6.d           shadow-         terminfo
aliases.db               cron.monthly             filesystems  hosts             ld.so.conf.d              modules-load.d        pki             rc.d            shells          tmpfiles.d
alternatives             crontab                  firewalld    hosts.allow       libaudit.conf             motd                  plymouth        rc.local        skel            trusted-key.key
anacrontab               cron.weekly              fonts        hosts.deny        libibverbs.d              mtab                  pm              rdma            sos.conf        tuned
asound.conf              crypttab                 fstab        img_version       libnl                     my.cnf                polkit-1        redhat-release  ssh             udev
at.deny                  csh.cshrc                gconf        infiniband        libreport                 my.cnf.d              popt.d          resolv.conf     ssl             updatedb.conf
audisp                   csh.login                gcrypt       infiniband-diags  libuser.conf              nanorc                postfix         rpc             statetab        usb_modeswitch.conf
audit                    dbus-1                   gdbinit      init.d            locale.conf               netconfig             ppp             rpm             statetab.d      uuid
bash_completion.d        default                  gdbinit.d    inittab           localtime                 NetworkManager        prelink.conf.d  rsyncd.conf     subgid          vconsole.conf
bashrc                   depmod.d                 GeoIP.conf   inputrc           login.defs                networks              printcap        rsyslog.conf    subgid-         vimrc
binfmt.d                 dhcp                     glvnd        iproute2          login.defs.rpmnew         nginx                 profile         rsyslog.d       subuid          virc
centos-release           DIR_COLORS               gnupg        iscsi             logrotate.conf            nsswitch.conf         profile.d       rwtab           subuid-         wgetrc
centos-release-upstream  DIR_COLORS.256color      GREP_COLORS  issue             logrotate.d               nsswitch.conf.bak     protocols       rwtab.d         sudo.conf       wpa_supplicant
chkconfig.d              DIR_COLORS.lightbgcolor  groff        issue.net         lsm                       nsswitch.conf.rpmnew  python          sasl2           sudoers         X11
chrony.conf              docker                   group        java              lvm                       ntp                   qcloudzone      scl             sudoers.d       xdg
chrony.keys              dracut.conf              group-       jvm               machine-id                ntp.conf              qemu-ga         securetty       sudo-ldap.conf  xinetd.d
cifs-utils               dracut.conf.d            grub2.cfg    jvm-commmon       magic                     openldap              rc0.d           security        sysconfig       yum
cloud                    e2fsck.conf              grub.d       kdump.conf        mail.rc                   opt                   rc1.d           selinux         sysctl.conf     yum.conf
containerd               egl                      gshadow      kernel            makedumpfile.conf.sample  os-release            rc2.d           services        sysctl.d        yum.repos.d
[root@centos-master etc]# cd /home/
[root@centos-master home]# cd ..
[root@centos-master /]# cd -
/home
[root@centos-master home]# cd -
/
[root@centos-master /]# 

 

 

6.认识[root@centos-master usr]# 

root:当前用户

@:at

centos-master:主机名

usr:当前目录

$:代表普通用户

#:代表root用户

7.切换用户:su

[root@centos-master usr]# su robin
[robin@centos-master usr]$ su root
密码：
su: 鉴定故障
[robin@centos-master usr]$ su root
密码：
[root@centos-master usr]# 

 8.创建目录：mkdir

mdkir dir  #创建单级目录

mkdir -p dir1/dir2/dir3 #创建多级目录 

 

 

[root@centos-master test]# mkdir dir
[root@centos-master test]# ls
dir
[root@centos-master test]# mkdir dir1/dir2/dir3 -p
[root@centos-master test]# tree
.
|-- dir
`-- dir1
    `-- dir2
        `-- dir3

4 directories, 0 files
[root@centos-master test]#

9.删除空目录：rmdir

[root@centos-master test]# rmdir --help
Usage: rmdir [OPTION]... DIRECTORY...
Remove the DIRECTORY(ies), if they are empty.

      --ignore-fail-on-non-empty
                  ignore each failure that is solely because a directory
                    is non-empty
  -p, --parents   remove DIRECTORY and its ancestors; e.g., 'rmdir -p a/b/c' is
                    similar to 'rmdir a/b/c a/b a'
  -v, --verbose   output a diagnostic for every directory processed
      --help     display this help and exit
      --version  output version information and exit

GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
For complete documentation, run: info coreutils 'rmdir invocation'
[root@centos-master test]# rmdir dir
[root@centos-master test]#

10.创建文件：touch

[root@centos-master dir]# touch --help
Usage: touch [OPTION]... FILE...
Update the access and modification times of each FILE to the current time.

A FILE argument that does not exist is created empty, unless -c or -h
is supplied.

A FILE argument string of - is handled specially and causes touch to
change the times of the file associated with standard output.

Mandatory arguments to long options are mandatory for short options too.
  -a                     change only the access time
  -c, --no-create        do not create any files
  -d, --date=STRING      parse STRING and use it instead of current time
  -f                     (ignored)
  -h, --no-dereference   affect each symbolic link instead of any referenced
                         file (useful only on systems that can change the
                         timestamps of a symlink)
  -m                     change only the modification time
  -r, --reference=FILE   use this file's times instead of current time
  -t STAMP               use [[CC]YY]MMDDhhmm[.ss] instead of current time
      --time=WORD        change the specified time:
                           WORD is access, atime, or use: equivalent to -a
                           WORD is modify or mtime: equivalent to -m
      --help     display this help and exit
      --version  output version information and exit

Note that the -d and -t options accept different time-date formats.

GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
For complete documentation, run: info coreutils 'touch invocation'
[root@centos-master dir]#

11.删除：rm

rm  -i #询问是否删除

rm -r #递归删除文件

rm -rf * 删除所有文件

[root@centos-master test]# touch test.txt
[root@centos-master test]# ls
dir  dir1  test.txt
[root@centos-master test]# rm --help
Usage: rm [OPTION]... FILE...
Remove (unlink) the FILE(s).

  -f, --force           ignore nonexistent files and arguments, never prompt
  -i                    prompt before every removal
  -I                    prompt once before removing more than three files, or
                          when removing recursively; less intrusive than -i,
                          while still giving protection against most mistakes
      --interactive[=WHEN]  prompt according to WHEN: never, once (-I), or
                          always (-i); without WHEN, prompt always
      --one-file-system  when removing a hierarchy recursively, skip any
                          directory that is on a file system different from
                          that of the corresponding command line argument
      --no-preserve-root  do not treat '/' specially
      --preserve-root   do not remove '/' (default)
  -r, -R, --recursive   remove directories and their contents recursively
  -d, --dir             remove empty directories
  -v, --verbose         explain what is being done
      --help     display this help and exit
      --version  output version information and exit

By default, rm does not remove directories.  Use the --recursive (-r or -R)
option to remove each listed directory, too, along with all of its contents.

To remove a file whose name starts with a '-', for example '-foo',
use one of these commands:
  rm -- -foo

  rm ./-foo

Note that if you use rm to remove a file, it might be possible to recover
some of its contents, given sufficient expertise and/or time.  For greater
assurance that the contents are truly unrecoverable, consider using shred.

GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
For complete documentation, run: info coreutils 'rm invocation'
[root@centos-master test]# rm -i test.txt
rm: remove regular empty file ‘test.txt’? y
[root@centos-master test]# tree
.
|-- dir
`-- dir1
    `-- dir2
        `-- dir3

4 directories, 0 files
[root@centos-master test]# rm -ri dir1
rm: descend into directory ‘dir1’? y
rm: descend into directory ‘dir1/dir2’? y
rm: remove directory ‘dir1/dir2/dir3’? y
rm: remove directory ‘dir1/dir2’? y
rm: remove directory ‘dir1’? y
[root@centos-master test]# rm -rfi *
rm: remove directory ‘dir’? y
[root@centos-master test]#

12.拷贝：cp

cp a.txt b.txt  如果b不存在就创建 如何b存在就覆盖

cp dir dir2 -r 递归操作 dir2如果不存在 则把dir的文件放入进去 如果存在则存入里面

cp dir/* dir2 -r 拷贝下面的

[root@centos-master test]# touch hello.c
[root@centos-master test]# vim hello.c
[root@centos-master test]# ls
hello.c
[root@centos-master test]# cat hello.c
hello world!
[root@centos-master test]# cp hello.c temp.c
[root@centos-master test]# cat temp.c
hello world!
[root@centos-master test]# vim test.txt
[root@centos-master test]# ls
hello.c  temp.c  test.txt
[root@centos-master test]# cat test.txt
test!
[root@centos-master test]# cp test.txt temp.c
cp: overwrite ‘temp.c’? y
[root@centos-master test]# cat temp.c
test!'
[root@centos-master test]# mkdir mytest
[root@centos-master test]# cd mytest/
[root@centos-master mytest]# touch test.txt
[root@centos-master mytest]# cd ../
[root@centos-master test]# ls
hello.c  mytest  temp.c  test.txt
[root@centos-master test]# cp -r  mytest/ newDir
[root@centos-master test]# ls
hello.c  mytest  newDir  temp.c  test.txt
[root@centos-master test]# tree newDir/
newDir/
`-- test.txt

0 directories, 1 file
[root@centos-master test]# cp -r  mytest/ newDir/
[root@centos-master test]# tree newDir/
newDir/
|-- mytest
|   `-- test.txt
`-- test.txt

1 directory, 2 files
[root@centos-master test]# cp --help
Usage: cp [OPTION]... [-T] SOURCE DEST
  or:  cp [OPTION]... SOURCE... DIRECTORY
  or:  cp [OPTION]... -t DIRECTORY SOURCE...
Copy SOURCE to DEST, or multiple SOURCE(s) to DIRECTORY.

Mandatory arguments to long options are mandatory for short options too.
  -a, --archive                same as -dR --preserve=all
      --attributes-only        don't copy the file data, just the attributes
      --backup[=CONTROL]       make a backup of each existing destination file
  -b                           like --backup but does not accept an argument
      --copy-contents          copy contents of special files when recursive
  -d                           same as --no-dereference --preserve=links
  -f, --force                  if an existing destination file cannot be
                                 opened, remove it and try again (this option
                                 is ignored when the -n option is also used)
  -i, --interactive            prompt before overwrite (overrides a previous -n
                                  option)
  -H                           follow command-line symbolic links in SOURCE
  -l, --link                   hard link files instead of copying
  -L, --dereference            always follow symbolic links in SOURCE
  -n, --no-clobber             do not overwrite an existing file (overrides
                                 a previous -i option)
  -P, --no-dereference         never follow symbolic links in SOURCE
  -p                           same as --preserve=mode,ownership,timestamps
      --preserve[=ATTR_LIST]   preserve the specified attributes (default:
                                 mode,ownership,timestamps), if possible
                                 additional attributes: context, links, xattr,
                                 all
  -c                           deprecated, same as --preserve=context
      --no-preserve=ATTR_LIST  don't preserve the specified attributes
      --parents                use full source file name under DIRECTORY
  -R, -r, --recursive          copy directories recursively
      --reflink[=WHEN]         control clone/CoW copies. See below
      --remove-destination     remove each existing destination file before
                                 attempting to open it (contrast with --force)
      --sparse=WHEN            control creation of sparse files. See below
      --strip-trailing-slashes  remove any trailing slashes from each SOURCE
                                 argument
  -s, --symbolic-link          make symbolic links instead of copying
  -S, --suffix=SUFFIX          override the usual backup suffix
  -t, --target-directory=DIRECTORY  copy all SOURCE arguments into DIRECTORY
  -T, --no-target-directory    treat DEST as a normal file
  -u, --update                 copy only when the SOURCE file is newer
                                 than the destination file or when the
                                 destination file is missing
  -v, --verbose                explain what is being done
  -x, --one-file-system        stay on this file system
  -Z                           set SELinux security context of destination
                                 file to default type
      --context[=CTX]          like -Z, or if CTX is specified then set the
                                 SELinux or SMACK security context to CTX
      --help     display this help and exit
      --version  output version information and exit

By default, sparse SOURCE files are detected by a crude heuristic and the
corresponding DEST file is made sparse as well.  That is the behavior
selected by --sparse=auto.  Specify --sparse=always to create a sparse DEST
file whenever the SOURCE file contains a long enough sequence of zero bytes.
Use --sparse=never to inhibit creation of sparse files.

When --reflink[=always] is specified, perform a lightweight copy, where the
data blocks are copied only when modified.  If this is not possible the copy
fails, or if --reflink=auto is specified, fall back to a standard copy.

The backup suffix is '~', unless set with --suffix or SIMPLE_BACKUP_SUFFIX.
The version control method may be selected via the --backup option or through
the VERSION_CONTROL environment variable.  Here are the values:

  none, off       never make backups (even if --backup is given)
  numbered, t     make numbered backups
  existing, nil   numbered if numbered backups exist, simple otherwise
  simple, never   always make simple backups

As a special case, cp makes a backup of SOURCE when the force and backup
options are given and SOURCE and DEST are the same name for an existing,
regular file.

GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
For complete documentation, run: info coreutils 'cp invocation'
[root@centos-master test]#

 12 ：查看目录：ls和tree

tree需要安装，yum install tree

ls -a显示所有的文件

ls -l 详细信息

第一个代表的是文件类型 如果是dr代表的是文件夹，如果是-代表的是普通文件 l代表软链接 s代表套接字 b块设备 c字符设备 p管道

后面九个字符：前面三个代表的是文件所有者对文件的操作权限 。中间三个文件所属组，后面三个其他人对文件的操作

数字代表链接数 root:代表文件所有者 后面的root：文件所属组 4096：目录的大小  后面就是文件最后的修改日期 最后是文件的名字

drwxr-xr-x 3 root root 4096 Dec 8 21:04 dir1

drwxr-xr-x 2 root root 4096 Dec 8 21:01 newDir
-rw-r--r-- 1 root root 0 Dec 8 21:01 test.txt

[root@centos-master test]# ls
dir1  newDir  test.txt
[root@centos-master test]# tree
.
|-- dir1
|   `-- dir2
|       `-- dir3
|-- newDir
`-- test.txt

4 directories, 1 file
[root@centos-master test]# ls -l
total 8
drwxr-xr-x 3 root root 4096 Dec  8 21:04 dir1
drwxr-xr-x 2 root root 4096 Dec  8 21:01 newDir
-rw-r--r-- 1 root root    0 Dec  8 21:01 test.txt
[root@centos-master test]# ls --help
Usage: ls [OPTION]... [FILE]...
List information about the FILEs (the current directory by default).
Sort entries alphabetically if none of -cftuvSUX nor --sort is specified.

Mandatory arguments to long options are mandatory for short options too.
  -a, --all                  do not ignore entries starting with .
  -A, --almost-all           do not list implied . and ..
      --author               with -l, print the author of each file
  -b, --escape               print C-style escapes for nongraphic characters
      --block-size=SIZE      scale sizes by SIZE before printing them; e.g.,
                               '--block-size=M' prints sizes in units of
                               1,048,576 bytes; see SIZE format below
  -B, --ignore-backups       do not list implied entries ending with ~
  -c                         with -lt: sort by, and show, ctime (time of last
                               modification of file status information);
                               with -l: show ctime and sort by name;
                               otherwise: sort by ctime, newest first
  -C                         list entries by columns
      --color[=WHEN]         colorize the output; WHEN can be 'never', 'auto',
                               or 'always' (the default); more info below
  -d, --directory            list directories themselves, not their contents
  -D, --dired                generate output designed for Emacs' dired mode
  -f                         do not sort, enable -aU, disable -ls --color
  -F, --classify             append indicator (one of */=>@|) to entries
      --file-type            likewise, except do not append '*'
      --format=WORD          across -x, commas -m, horizontal -x, long -l,
                               single-column -1, verbose -l, vertical -C
      --full-time            like -l --time-style=full-iso
  -g                         like -l, but do not list owner
      --group-directories-first
                             group directories before files;
                               can be augmented with a --sort option, but any
                               use of --sort=none (-U) disables grouping
  -G, --no-group             in a long listing, don't print group names
  -h, --human-readable       with -l, print sizes in human readable format
                               (e.g., 1K 234M 2G)
      --si                   likewise, but use powers of 1000 not 1024
  -H, --dereference-command-line
                             follow symbolic links listed on the command line
      --dereference-command-line-symlink-to-dir
                             follow each command line symbolic link
                               that points to a directory
      --hide=PATTERN         do not list implied entries matching shell PATTERN
                               (overridden by -a or -A)
      --indicator-style=WORD  append indicator with style WORD to entry names:
                               none (default), slash (-p),
                               file-type (--file-type), classify (-F)
  -i, --inode                print the index number of each file
  -I, --ignore=PATTERN       do not list implied entries matching shell PATTERN
  -k, --kibibytes            default to 1024-byte blocks for disk usage
  -l                         use a long listing format
  -L, --dereference          when showing file information for a symbolic
                               link, show information for the file the link
                               references rather than for the link itself
  -m                         fill width with a comma separated list of entries
  -n, --numeric-uid-gid      like -l, but list numeric user and group IDs
  -N, --literal              print raw entry names (don't treat e.g. control
                               characters specially)
  -o                         like -l, but do not list group information
  -p, --indicator-style=slash
                             append / indicator to directories
  -q, --hide-control-chars   print ? instead of nongraphic characters
      --show-control-chars   show nongraphic characters as-is (the default,
                               unless program is 'ls' and output is a terminal)
  -Q, --quote-name           enclose entry names in double quotes
      --quoting-style=WORD   use quoting style WORD for entry names:
                               literal, locale, shell, shell-always, c, escape
  -r, --reverse              reverse order while sorting
  -R, --recursive            list subdirectories recursively
  -s, --size                 print the allocated size of each file, in blocks
  -S                         sort by file size
      --sort=WORD            sort by WORD instead of name: none (-U), size (-S),
                               time (-t), version (-v), extension (-X)
      --time=WORD            with -l, show time as WORD instead of default
                               modification time: atime or access or use (-u)
                               ctime or status (-c); also use specified time
                               as sort key if --sort=time
      --time-style=STYLE     with -l, show times using style STYLE:
                               full-iso, long-iso, iso, locale, or +FORMAT;
                               FORMAT is interpreted like in 'date'; if FORMAT
                               is FORMAT1<newline>FORMAT2, then FORMAT1 applies
                               to non-recent files and FORMAT2 to recent files;
                               if STYLE is prefixed with 'posix-', STYLE
                               takes effect only outside the POSIX locale
  -t                         sort by modification time, newest first
  -T, --tabsize=COLS         assume tab stops at each COLS instead of 8
  -u                         with -lt: sort by, and show, access time;
                               with -l: show access time and sort by name;
                               otherwise: sort by access time
  -U                         do not sort; list entries in directory order
  -v                         natural sort of (version) numbers within text
  -w, --width=COLS           assume screen width instead of current value
  -x                         list entries by lines instead of by columns
  -X                         sort alphabetically by entry extension
  -1                         list one file per line

SELinux options:

  --lcontext                 Display security context.   Enable -l. Lines
                             will probably be too wide for most displays.
  -Z, --context              Display security context so it fits on most
                             displays.  Displays only mode, user, group,
                             security context and file name.
  --scontext                 Display only security context and file name.
      --help     display this help and exit
      --version  output version information and exit

SIZE is an integer and optional unit (example: 10M is 10*1024*1024).  Units
are K, M, G, T, P, E, Z, Y (powers of 1024) or KB, MB, ... (powers of 1000).

Using color to distinguish file types is disabled both by default and
with --color=never.  With --color=auto, ls emits color codes only when
standard output is connected to a terminal.  The LS_COLORS environment
variable can change the settings.  Use the dircolors command to set it.

Exit status:
 0  if OK,
 1  if minor problems (e.g., cannot access subdirectory),
 2  if serious trouble (e.g., cannot access command-line argument).

GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
For complete documentation, run: info coreutils 'ls invocation'
[root@centos-master test]# tree --help
usage: tree [-acdfghilnpqrstuvxACDFQNSUX] [-H baseHREF] [-T title ] [-L level [-R]]
        [-P pattern] [-I pattern] [-o filename] [--version] [--help] [--inodes]
        [--device] [--noreport] [--nolinks] [--dirsfirst] [--charset charset]
        [--filelimit[=]#] [--si] [--timefmt[=]<f>] [<directory list>]
  ------- Listing options -------
  -a            All files are listed.
  -d            List directories only.
  -l            Follow symbolic links like directories.
  -f            Print the full path prefix for each file.
  -x            Stay on current filesystem only.
  -L level      Descend only level directories deep.
  -R            Rerun tree when max dir level reached.
  -P pattern    List only those files that match the pattern given.
  -I pattern    Do not list files that match the given pattern.
  --noreport    Turn off file/directory count at end of tree listing.
  --charset X   Use charset X for terminal/HTML and indentation line output.
  --filelimit # Do not descend dirs with more than # files in them.
  --timefmt <f> Print and format time according to the format <f>.
  -o filename   Output to file instead of stdout.
  --du          Print directory sizes.
  --prune       Prune empty directories from the output.
  -------- File options ---------
  -q            Print non-printable characters as '?'.
  -N            Print non-printable characters as is.
  -Q            Quote filenames with double quotes.
  -p            Print the protections for each file.
  -u            Displays file owner or UID number.
  -g            Displays file group owner or GID number.
  -s            Print the size in bytes of each file.
  -h            Print the size in a more human readable way.
  --si          Like -h, but use in SI units (powers of 1000).
  -D            Print the date of last modification or (-c) status change.
  -F            Appends '/', '=', '*', '@', '|' or '>' as per ls -F.
  --inodes      Print inode number of each file.
  --device      Print device ID number to which each file belongs.
  ------- Sorting options -------
  -v            Sort files alphanumerically by version.
  -r            Sort files in reverse alphanumeric order.
  -t            Sort files by last modification time.
  -c            Sort files by last status change time.
  -U            Leave files unsorted.
  --dirsfirst   List directories before files (-U disables).
  ------- Graphics options ------
  -i            Don't print indentation lines.
  -A            Print ANSI lines graphic indentation lines.
  -S            Print with ASCII graphics indentation lines.
  -n            Turn colorization off always (-C overrides).
  -C            Turn colorization on always.
  ------- XML/HTML options -------
  -X            Prints out an XML representation of the tree.
  -H baseHREF   Prints out HTML format with baseHREF as top directory.
  -T string     Replace the default HTML title and H1 header with string.
  --nolinks     Turn off hyperlinks in HTML output.
  ---- Miscellaneous options ----
  --version     Print version and exit.
  --help        Print usage and this help message and exit.
[root@centos-master test]#