LINUX文件管理. - EDUUNIXPPT课件

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UNIX文件系统文件类型
• Directory --> catalogue of file name • Normal file --> format of data
–source file –text file
• Symbolic link --> a pointer to another file • Special file --> use for device controller in
kernel • Named pipe --> communication channel which
can be used by serveral processes(may be irrelevant) in order to exchange data
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硬链接（Hard Link）
root
[root@localhost link]# rm a
rm: remove `a'? y
[root@localhost link]# ls -l
total 1
-rw-r--r-- 1 root
root
667 Oct 15 13:39 a
667 Oct 15 13:39 a 667 Oct 15 13:39 b
total 0
lrwxrwxrwx 1 root
root
[root@localhost symlink]# cat b
cat: b: No such file or directory
667 Oct 15 13:39 a
667 Oct 15 13:39 a 1 Oct 15 14:20 b -> a
Linux File System
• 文件系统 • VFS
VFS的作用 基于VFS的文件访问 VFS重要数据结构 • 文件系统的注册与安装 • ext2、ext3文件系统 • 文件操作 • proc文件系统 • CRAMFS文件系统
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各种各样的文件系统
Windows FAT16,FAT32, NTFS 传统UNIX: UFS (Unix File System) BSD文件系统FFS(Fast File System) Proc File System：只存在于内存中 Linux File System
/lib - contain shared library that is required by system program
/tmp - contain system temporary file
/opt - Add-on application software packages
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– ext2 ( is first introduced in kernel 2.0.x ) – reiserfs ( is first introduced in kernel 2.2.x ) – ext3 ( is first introduced in kernel 2.4.x ,default in RedHat now) – xfs (from SGI ) – Jfs (from IBM ) 嵌入式小型文件系统 CRAMFS JFFS2
[root@localhost symlink]# ls -l
total 1
-rw-r--r-- 1 root
root
lrwxrwxrwx 1 root
root
[root@localhost yy]# rm a
rm: remove `a'? y
[root@localhost symlink]# ls -l
/bin - Essential command binaries for both root and ord. users
/sbin - Essential system binaries for administrator
/dev - keep all device files
/usr - keep all user binary and X library
2020/1布局
To comply with FSSTND(File System STaNDard):
/
- first of mount point in linux
/etc - keep linux default configuration
/boot - keep important linux booting files(can be a separate file system)
[root@localhost link]# ls -l
total 1
-rw-r--r-- 1 root
root
[root@localhost link]# ln a b
[root@localhost link]# ls -l
total 2
-rw-r--r-- 2 root
root
-rw-r--r-- 2 root
/home - keep user home directory
/proc - is pseudo file system for tracking running process and state of linux system
/var - keeping mail, log file and printer spooling
667 Oct 15 13:39 b
/root/link
inode
a
b
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符号链接（Symbolic link）
[root@localhost symlink]# ls -l
total 1
-rw-r--r-- 1 root
root
[root@localhost symlink]# ln -s a b
1 Oct 15 14:20 b -> a
/root/link
inode
a
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VFS(Virtual FileSystem)的作用
User Programs System Call Interface
Virtual File System
Ext2 Ext3
...
Buffer Cache Device Driver