简介
浏览他人技术博客的时候，会看到用文本列出漂亮的文件夹目录，实际大部分都是使用了Linux下的Tree命令。以下简单介绍下Tree命令的格式和例子。
安装
一般Linux系统是不自带Tree命令工具的，可以通过以下命令获取和安装：
sudo apt-get install tree格式
通过上述命令获取后，可以通过一下命令显示使用方法：
tree --help显示如下：
usage: tree [-acdfghilnpqrstuvxACDFJQNSUX] [-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>]
[--sort[=]<name>] [--matchdirs] [--ignore-case] [--] [<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.
--ignore-case Ignore case when pattern matching.
--matchdirs Include directory names in -P pattern matching.
--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.
-------- 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.
-t Sort files by last modification time.
-c Sort files by last status change time.
-U Leave files unsorted.
-r Reverse the order of the sort.
--dirsfirst List directories before files (-U disables).
--sort X Select sort: name,version,size,mtime,ctime.
------- Graphics options ------
-i Don't print indentation lines.
-A Print ANSI lines graphic indentation lines.
-S Print with CP437 (console) graphics indentation lines.
-n Turn colorization off always (-C overrides).
-C Turn colorization on always.
------- XML/HTML/JSON options -------
-X Prints out an XML representation of the tree.
-J Prints out an JSON 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.
-- Options processing terminator.
可以看到最新的Tree命令工具在老版本基础上已经做了很多扩展，分别有Listing、File 、Graphics、 XML/HTML/JSON 、
举例
虽然现在功能越来越强大，但是对于大部分人来说常用的并不多，以下举几个常用的例子：
显示全部层级的目录和文件
tree -a.
├── 1.txt
├── demo1
│ ├── CMakeCache.txt
│ ├── CMakeFiles
│ │ ├── 3.5.1
│ │ │ ├── CMakeCCompiler.cmake
│ │ │ ├── CMakeCXXCompiler.cmake
│ │ │ ├── CMakeDetermineCompilerABI_C.bin
│ │ │ ├── CMakeDetermineCompilerABI_CXX.bin
│ │ │ ├── CMakeSystem.cmake
│ │ │ ├── CompilerIdC
│ │ │ │ ├── a.out
│ │ │ │ └── CMakeCCompilerId.c
│ │ │ └── CompilerIdCXX
│ │ │ ├── a.out
│ │ │ └── CMakeCXXCompilerId.cpp
│ │ ├── cmake.check_cache
│ │ ├── CMakeDirectoryInformation.cmake
│ │ ├── CMakeOutput.log
│ │ ├── CMakeTmp
│ │ ├── Demo.dir
│ │ │ ├── build.make
│ │ │ ├── cmake_clean.cmake
│ │ │ ├── CXX.includecache
│ │ │ ├── DependInfo.cmake
│ │ │ ├── depend.internal
│ │ │ ├── depend.make
│ │ │ ├── flags.make
│ │ │ ├── link.txt
│ │ │ ├── main.cc.o
│ │ │ └── progress.make
│ │ ├── feature_tests.bin
│ │ ├── feature_tests.c
│ │ ├── feature_tests.cxx
│ │ ├── Makefile2
│ │ ├── Makefile.cmake
│ │ ├── progress.marks
│ │ └── TargetDirectories.txt
│ ├── cmake_install.cmake
│ ├── CMakeLists.txt
│ ├── Demo
│ ├── main.cc
│ └── Makefile
└── demo2显示指定层级的目录和文件
tree -L 2 // -L 指定目录深度
.
├── 1.txt
├── demo1
│ ├── CMakeCache.txt
│ ├── CMakeFiles
│ ├── cmake_install.cmake
│ ├── CMakeLists.txt
│ ├── Demo
│ ├── main.cc
│ └── Makefile
└── demo2显示目录/文件地址
tree -L 2 -f.
├── ./1.txt
├── ./demo1
│ ├── ./demo1/CMakeCache.txt
│ ├── ./demo1/CMakeFiles
│ ├── ./demo1/cmake_install.cmake
│ ├── ./demo1/CMakeLists.txt
│ ├── ./demo1/Demo
│ ├── ./demo1/main.cc
│ └── ./demo1/Makefile
└── ./demo2仅显示目录不显示文件
tree -L3 -d.
├── demo1
│ └── CMakeFiles
│ ├── 3.5.1
│ ├── CMakeTmp
│ └── Demo.dir
└── demo2区分目录和文件
tree -L 2 -F.
├── 1.txt
├── demo1/
│ ├── CMakeCache.txt
│ ├── CMakeFiles/
│ ├── cmake_install.cmake
│ ├── CMakeLists.txt
│ ├── Demo*
│ ├── main.cc
│ └── Makefile
└── demo2/不显示目录树中的层级线
tree -L 2 -i.
1.txt
demo1
CMakeCache.txt
CMakeFiles
cmake_install.cmake
CMakeLists.txt
Demo
main.cc
Makefile
demo2显示XML格式
tree -L 2 -X<?xml version="1.0" encoding="UTF-8"?>
<tree>
<directory name=".">
<file name="1.txt"></file>
<directory name="demo1">
<file name="CMakeCache.txt"></file>
<directory name="CMakeFiles">
</directory>
<file name="cmake_install.cmake"></file>
<file name="CMakeLists.txt"></file>
<file name="Demo"></file>
<file name="main.cc"></file>
<file name="Makefile"></file>
</directory>
<directory name="demo2">
</directory>
</directory>
<report>
<directories>3</directories>
<files>7</files>
</report>
</tree>
保存内容
tree -L 2 >> 1.txt总结
作为常用命令，Tree命令在平时使用中可以帮助我们快速了解当前的目录/文件结构，也可以辅助写处更漂亮的博客。