◊ basic framework:
a) What is a file system
b) File Type
c) Mount 与 umount
d) soft and hard-wired connection
1. What is the file system
File system: disk method to organize your files, such as NTFS under windows, FAT
system V under LINUX, ext2, ext3
After the buy back of the hard drive to partition and format to use, hard disk partition information stored in the hard disk 0 track 0 sector, another hard disk usage information and management information is also stored on the hard disk.
Linux system is a file system for each partition.
Linux system in a partition following the path does not necessarily belong to the partition, a partition because this path can mount other partitions (file system).
♦ Linux system directory structure:
/ Etc: Configuration Files
/ Sbin: System Manager
/ Dev: device file
/ Bin: common commands
/ Boot: the use of startup files
/ Lib: shared dynamic link library
/ Root: the user's home directory
/ Home: each user's home directory
/ Usr: storage applications, / usr / lib (library) / usr / include (header file)
2, File Type:
1) Ordinary file: (-) into text and binary files
2) catalog file: (d)
3) Device file: generally stored in the / dev directory
/ Dev / tty1 (c) character device file
/ Dev / sda1 (b) block device file
4) Soft connection file: start with l, back to "->" pointing to the attached file
3、 mount 与 umount
If you want to use a file system, you must first mount the file system
1) Mount + name + path device:
The device name can be viewed with the fdisk -l
Path is typically mounted to / mnt /
2) Umount + device name / path mount point: Uninstall
3) zoning status of the Linux operating system:
• boot partition
• The root partition
• The system's temporary swap file system (tmpfs), for the use of memory, the equivalent of virtual memory
Features: When the system is turned off, there is the area of the file will disappear, but its access speed is faster
Fdisk -l to view the current status of partition
Df -h to see mount point of each partition
4, soft connection with hard-wired
Every file on the hard disk should have a inode to record the management information file, a partition there are many files (stored in the file data area), there are many indexing node (stored in the inode area), each index node there is a inode number ( also called do i node number ), the inode number is stored in an array ( inode number array ).
By file name, you can find the inode number to find the inode, and finally found the appropriate files.
1 ) hard-wired : the directory itself is a file, directory to store many files on the file name and inode number, file name and index of each node is known as a hard link
Ln: Creating a connection
Inode number Ls -i (inode) to view the file / directory
2) flexible connection (also called symbolic link)
Soft connection can be established across partitions, but not hard-wired.
Ln -s to create a soft link
Opens a file with the soft link ls indirect way open, but is hard-wired directly to open the file corresponding to the i-node number.
3) soft and hard-wired connection differences :
Open indirectly characteristics: efficiency is lower than directly open some, but it can be across partitions created.
Reproduced in: https: //www.cnblogs.com/zkw-2014/p/4417747.html