man查詢括號中的數字含義

        當我們在使用man查詢命令時會發現命令後面會有一個數字，如ls命令後面的1，shutdown後面的8。

LS(1)                            User Commands                           LS(1)

NAME
       ls - list directory contents
...... 

shutdown(8)                 System Manager's Manual                shutdown(8)

NAME
       shutdown - bring the system down
...... 

            那麼這些數字有什麼含義呢？使用man man命令可以看到一下的內容。

......
The table below shows the section numbers of the manual followed by the
       types of pages they contain.

       1   Executable programs or shell commands
       2   System calls (functions provided by the kernel)
       3   Library calls (functions within program libraries)
       4   Special files (usually found in /dev)
       5   File formats and conventions eg /etc/passwd
       6   Games
       7   Miscellaneous  (including  macro  packages  and  conventions), e.g.
           man(7), groff(7)
       8   System administration commands (usually only for root)
       9   Kernel routines [Non standard]
...... 

        一般我們使用較多的是1，5，8

                1.用戶在Shell環境中可以操作的命令或可執行文件。

                5.配置文件或某些文件格式。

                8.系統管理員可用的管理命令。