UNIX文件系统
inode
Contains file attributes, metadata of file, pointer structure
file
Can be considered a table with 2 columns, filename and its inode, inode points to the raw data blocks on the block device
directory
just a special file, container for other filenames. It contains an array of filenames and inode numbers for each filename. Also it describes the relationship between parent and children
symbolic link VS hard link
dentry (directory entries)
On typical ext4 file system (what most people use), the default inode size is 256 bytes, block size is 4096 bytes.
A directory is just a special file which contains an array of filenames and inode numbers. When the directory was created, the file system allocated 1 inode to the directory with a “filename” (dir name in fact). The inode points to a single data block (minimum overhead), which is 4096 bytes. That’s why you see 4096 / 4.0K when using ls.
一个目录仅是一个文件: 包含
You can get the details by using tune2fs & dumpe2fs