/bin , /sbin , /usr/sbin , /usr/local/sbin 的区别

usr 是 UNIX Software Resource 的缩写，也就是 Unix操作系统软件资源 所放置的目录。

一 /bin:Essential user command binaries(for use by all users)

　　1 Purpose

　　/bin contains commands that may be used by both the system administrator and by users,but which are required when no other filesystems are mounted(e.g. in single user mode).It may also

contain commands which are used indirectly by scripts.

　　2 Requirements

　　There must be no subdirectories in /bin,

　　The following commands,or symbolic links to commands,are required in /bin.

　　cat

　　chgrp

　　chmod

　　chown

　　cp

　　date

　　dd

　　df

　　dmesg

　　echo

　　false

　　hostname

　　kill

　　ln

　　login

　　ls

　　mkdir

　　mknod

　　more

　　mount

　　mv

　　ps

　　pwd

　　rm

　　rmdir

　　sed

　　sh

　　stty

　　su

　　sync

　　true

　　umount

　　uname

二 /sbin:System binaries

　　1 Purpose

　　Utilities used for system administration (and other root-only commands) are stored in /sbin, /usr/sbin, and /usr/local/sbin. /sbin contains binaries essential for booting, restoring, recovering, and/or repairing the system in addition to the binaries in /bin. Programs executed after /usr is known to be mounted (when there are no problems) are generally placed into /usr/sbin. Locally-installed system administration programs should be placed into /usr/local/sbin.

　　2 Requirements　　

　　　　shutdown

　　

三 /usr/sbin:Non-essential standard system binaries

　　1 Purpose

　　This directory contains any non-essential binaries used exclusively by the system administrator. System administration programs that are required for system repair, system recovery, mounting /usr, or other essential functions must be placed in /sbin instead.

　　

四  /usr/local/sbin

五 /usr/bin 绝大部分用户可使用命令都放在这里。