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. ＃显示所有文件
-d List directories only. ＃仅显示文件件，不显示文件
-l Follow symbolic links like directories.
-f Print the full path prefix for each file.
-L level Descend only level directories deep. ＃显示N层目录
-R Rerun tree when max dir level reached.
-P pattern List only those files that match the pattern given. #只显示符合"pattern"的文件或目录名称
-I pattern Do not list files that match the given pattern. #不显示符合范本样式的文件或目录名称 tree -I "*.c"
--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 '?'. #用"?"号取代控制字符，列出文件和目录名称
-N Print non-printable characters as is. #直接列出文件和目录名称，包括控制字符
-Q Quote filenames with double quotes.
-p Print the protections for each file. #列出权限标示
-u Displays file owner or UID number. #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
-s Print the size in bytes of each file. #列出文件或目录大小
-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. #列出文件或目录的更改时间
-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. #按字母数字排序
-r Sort files in reverse alphanumeric order. ＃按字母数字倒序排序
-t Sort files by last modification time. # 按最后修改时间排序的文件
-c Sort files by last status change time. # 按最近的修改状态排序
-U Leave files unsorted. ＃分类整理排序
--dirsfirst List directories before files (-U disables).
------- Graphics options ------
-i Don't print indentation lines. #不以阶梯状列出文件或目录名称
-A Print ANSI lines graphic indentation lines. #使用ASNI绘图字符显示树状图而非以ASCII字符组合
-S Print with ASCII graphics indentation lines.
-n Turn colorization off always (-C overrides). #不在文件和目录清单加上色彩
-C Turn colorization on always. #在文件和目录清单加上色彩，便于区分各种类型
------- 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.