本篇文章主要介绍 Android 开发中的部分知识点，通过阅读本篇文章，您将收获以下内容:

一、cd 命令

二、--help 命令

三、 ls 命令

四、touch 命令

五、mkdir命令

六、pwd 命令

七、echo 命令

八、cat 命令

九、Tab 键

十、vi 或者vim 命令

十一、rm 命令

十二、mv 命令

十三、cp 命令

十四、find 命令

十五、grep 命名

十六、chmod 命令

十七、压缩与解压命令

cd 命令是 Linux常用命令之一linux命令大全，主要用于进入目录（相当于windows的文件夹）。

比如我想进入TestLinuxCommond这个目录。

可以使用cd TestLinuxCommond/

wangjie@ubuntu:~$ cd TestLinuxCommond/
wangjie@ubuntu:~/TestLinuxCommond$ 

比如我想退出TestLinuxCommond这个目录。

可以使用cd ..

wangjie@ubuntu:~/TestLinuxCommond$ cd ..
wangjie@ubuntu:~$ 

如果想退两层目录，可以使用cd ../..

wangjie@ubuntu:~/TestLinuxCommond/testmv/test$ ls
wangjie@ubuntu:~/TestLinuxCommond/testmv/test$ cd ../..
wangjie@ubuntu:~/TestLinuxCommond$ 

当我们不知道一个命令如何使用时候，可以使用 --help 查看这个命令是干嘛的。

--help相当于用户命令帮忙的手册。

比如 我想看看 cd命令是如何使用的，可以使用cd ---help

wangjie@ubuntu:~/TestLinuxCommond$ cd ---help
-bash: cd: --: invalid option
cd: usage: cd [-L|[-P [-e]] [-@]] [dir]
wangjie@ubuntu:~/TestLinuxCommond$ 

比如 我想看看 ls命令是如何使用的，使用参数如何，可以使用ls ---help

wangjie@ubuntu:~/TestLinuxCommond$ 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 defaults to 'always'
                               or can be 'never' or 'auto'.  More info below
  -d, --directory            list directory entries instead of contents,
                               and do not dereference symbolic links
  -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.
                               augment 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            use 1024-byte blocks
  -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 non graphic characters
      --show-control-chars   show non graphic characters as-is (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,
                             extension -X, size -S, time -t, version -v
      --time=WORD            with -l, show time as WORD instead of modification
                             time: atime -u, access -u, use -u, ctime -c,
                             or status -c; 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, +FORMAT.
                             FORMAT is interpreted like 'date'; if FORMAT is
                             FORMAT1<newline>FORMAT2, 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
  -Z, --context              print any SELinux security context of each file
  -1                         list one file per line
      --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).
Report ls bugs to bug-coreutils@gnu.org
GNU coreutils home page: <http://www.gnu.org/software/coreutils/>
General help using GNU software: <http://www.gnu.org/gethelp/>
For complete documentation, run: info coreutils 'ls invocation'
wangjie@ubuntu:~/TestLinuxCommond$