在文本处理的工作中，统计文件的行数，单词数和字符数非常有用。而对于开发人员本身来说，统计LOC(line of code ,代码行数)是一件重要的工作。linux中有什么命令可以帮助我们做统计呢?没错，就是wc，不是厕所的意思啊，是Word Count的缩写。
当作好统计时，又需要写个开发的文档，特别是项目比较大的时候，如果将目录和文件系统以图形化的树状层次结构描述，在以后的维护过程将更加清晰明了，下面将同样将要介绍的还有tree命令.
一、wc命令详解
首先，输入man wc 查看wc 的指导手册
NAME
wc - print newline, word, and byte counts for each file SYNOPSIS
wc [OPTION]... [FILE]...
wc [OPTION]... --files0-from=F DESCRIPTION
Print newline, word, and byte counts for each FILE, and a total line if more than one FILE is specified. With no FILE, or
when FILE is -, read standard input. A word is a non-zero-length sequence of characters delimited by white space. The
options below may be used to select which counts are printed, always in the following order: newline, word, character,
byte, maximum line length. -c, --bytes
print the byte counts -m, --chars
print the character counts -l, --lines
print the newline counts --files0-from=F
read input from the files specified by NUL-terminated names in file F; If F is - then read names from standard input -L, --max-line-length
print the length of the longest line -w, --words
print the word counts --help display this help and exit --version
output version information and exit
语法：
wc [OPTION]... [FILE]...
wc [OPTION]... --files0-from=F
参数－实例：
下面将通过实例介绍各参数的含义和作用：
用到的test.txt
amosli@amosli-pc:~/learn/wc$ cat test.txt
Print newline, word, and byte counts for each FILE, and a total line if more than one FILE is specified. With no FILE, or
when FILE is -, read standard input. A word is a non-zero-length sequence of characters delimited by white space. The
options below may be used to select which counts are printed, always in the following order: newline, word, character,
byte, maximum line length.
１、-c参数，统计字节数,字符数
amosli@amosli-pc:~/learn/wc$ wc -c test.txt
test.txt
2.-l参数，统计行数
amosli@amosli-pc:~/learn/wc$ wc -l test.txt
test.txt
3.-w参数，统计单词数
amosli@amosli-pc:~/learn/wc$ wc -w test.txt
test.txt
4.-L参数，统计最长行的长度
amosli@amosli-pc:~/learn/wc$ wc -L test.txt
test.txt
5.-m参数，统计字母数
amosli@amosli-pc:~/learn/wc$ wc -m test.txt
test.txt
6.不加参数
amosli@amosli-pc:~/learn/wc$ wc test.txt
test.txt
分别表示行数，单词数，字符数
7.使用标准输入进行统计
amosli@amosli-pc:~/learn/wc$ echo "hi_amos" | wc -m
二、tree命令详解
首先，sudo apt-get install tree安装一下tree命令
下面将输入tree --help查看提示信息:
amosli@amosli-pc:~/learn$ tree --help
usage: tree [-adfghilnpqrstuvxACDFNS] [-H baseHREF] [-T title ] [-L level [-R]]
[-P pattern] [-I pattern] [-o filename] [--version] [--help] [--inodes]
[--device] [--noreport] [--nolinks] [--dirsfirst] [--charset charset]
[--filelimit #] [<directory list>]
-a All files are listed.
-d List directories only.
-l Follow symbolic links like directories.
-f Print the full path prefix for each file.
-i Don't print indentation lines.
-q Print non-printable characters as '?'.
-N Print non-printable characters as is.
-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.
-D Print the date of last modification.
-F Appends '/', '=', '*', or '|' as per ls -F.
-v Sort files alphanumerically by version.
-r Sort files in reverse alphanumeric order.
-t Sort files by last modification time.
-x Stay on current filesystem only.
-L level Descend only level directories deep.
-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.
-P pattern List only those files that match the pattern given.
-I pattern Do not list files that match the given pattern.
-H baseHREF Prints out HTML format with baseHREF as top directory.
-T string Replace the default HTML title and H1 header with string.
-R Rerun tree when max dir level reached.
-o file Output to file instead of stdout.
--inodes Print inode number of each file.
--device Print device ID number to which each file belongs.
--noreport Turn off file/directory count at end of tree listing.
--nolinks Turn off hyperlinks in HTML output.
--dirsfirst List directories before files.
--charset X Use charset X for HTML and indentation line output.
--filelimit # Do not descend dirs with more than # files in them.
语法：
tree [-adfghilnpqrstuvxACDFNS] [-H baseHREF] [-T title ] [-L level [-R]]
[-P pattern] [-I pattern] [-o filename] [--version] [--help] [--inodes]
[--device] [--noreport] [--nolinks] [--dirsfirst] [--charset charset]
[--filelimit #] [<directory list>]
参数－实例：
-a 显示所有文件和目录。
-A 使用ASNI绘图字符显示树状图而非以ASCII字符组合。
-C 在文件和目录清单加上色彩，便于区分各种类型。
-d 显示目录名称而非内容。
-D 列出文件或目录的更改时间。
-f 在每个文件或目录之前，显示完整的相对路径名称。
-F 在执行文件，目录，Socket，符号连接，管道名称名称，各自加上"*","/","=","@","|"号。
-g 列出文件或目录的所属群组名称，没有对应的名称时，则显示群组识别码。
-i 不以阶梯状列出文件或目录名称。
-I 不显示符合范本样式的文件或目录名称。
-l 如遇到性质为符号连接的目录，直接列出该连接所指向的原始目录。
-n 不在文件和目录清单加上色彩。
-N 直接列出文件和目录名称，包括控制字符。
-p 列出权限标示。
-P 只显示符合范本样式的文件或目录名称。
-q 用"?"号取代控制字符，列出文件和目录名称。
-s 列出文件或目录大小。
-t 用文件和目录的更改时间排序。
-u 列出文件或目录的拥有者名称，没有对应的名称时，则显示用户识别码。
-x 将范围局限在现行的文件系统中，若指定目录下的某些子目录，其存放于另一个文件系统上，则将该子目录予以排除在寻找范围外。
１、不输入任何参数使用tree命令
amosli@amosli-pc:~/learn/re$ tree
.
├── d1
│ └── d2
│ └── d3
│ └── a.txt
├── d2
│ └── d2
│ └── d3
│ └── a.txt
├── db
│ └── dc
├── dd
│ └── db
├── test.sh
├── version1.txt
├── version2.txt
└── version.patch directories, files
２、-P参数,对样式进行筛选
如，筛选.sh结尾的文件
amosli@amosli-pc:~/learn/re$ tree . -P "*.sh"
.
├── d1
│ └── d2
│ └── d3
├── d2
│ └── d2
│ └── d3
├── db
│ └── dc
├── dd
│ └── db
└── test.sh
３、－h参数，打印出文件和目录的大小
amosli@amosli-pc:~/learn/re$ tree -h
.
├── [.0K] d1
│ └── [.0K] d2
│ └── [.0K] d3
│ └── [ ] a.txt
├── [.0K] d2
│ └── [.0K] d2
│ └── [.0K] d3
│ └── [ ] a.txt
├── [.0K] db
│ └── [.0K] dc
├── [.0K] dd
│ └── [.0K] db
├── [ ] test.sh
├── [ ] version1.txt
├── [ ] version2.txt
└── [ ] version.patch directories, files
4、-d参数，只显示目录
amosli@amosli-pc:~/learn/re$ tree -d
.
├── d1
│ └── d2
│ └── d3
├── d2
│ └── d2
│ └── d3
├── db
│ └── dc
└── dd
└── db directories
５、-D参数，显示文件修改日期
amosli@amosli-pc:~/learn/re$ tree -D
.
├── [Dec :] d1
│ └── [Dec :] d2
│ └── [Dec :] d3
│ └── [Dec :] a.txt
├── [Dec :] d2
│ └── [Dec :] d2
│ └── [Dec :] d3
│ └── [Dec :] a.txt
├── [Dec :] db
│ └── [Dec :] dc
├── [Dec :] dd
│ └── [Dec :] db
├── [Dec :] test.sh
├── [Dec :] version1.txt
├── [Dec :] version2.txt
└── [Dec :] version.patch directories, files
6、-i参数，不以阶梯状显示
amosli@amosli-pc:~/learn/re$ tree -i
.
d1
d2
d3
a.txt
d2
d2
d3
a.txt
db
dc
dd
db
test.sh
version1.txt
version2.txt
version.patch directories, files