Linux命令ls --color 和ls -color 分别是干什么用的有什么区别?注：前者color前面有两个“-”

ls -color
是指 ls -c -o -l -o -r组合的意思
-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
-l use a long listing format
-o like -l,but do not list group information
-r,--reverse reverse order while sorting
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ls --color是颜色选项
--color[=WHEN] control whether color is used to distinguish file
types.WHEN may be `never',`always',or `auto'