Session 29: Filesystem structure

Multi-block files (Section 5.3.1)
  linked list
  file access table
  array (i-nodes)
Directory organization (Section 5.3.2)
Free space tracking (Section 5.3.3)
  linked list

Multi-block files

Linked list

File access table

Array (i-nodes)

A final alternative is to have an array of block numbers in the file. This provides an easy way to jump immediately to any location in the file. It also renders unnecessary the large

Directory organization


 0- 7: filename
 8-10: extension
  11 : attributes
12-21: unused (reserved for later versions)
22-23: time
23-24: date
25-26: number of first block in file
27-31: size of file (in bytes)


 0- 1: i-node number
 2-15: filename
 0- 1: permissions and file type
 2- 3: number of links to i-node
 4- 5: user id
 6- 7: group id
 8-11: file size (in bytes)
12-15: time of last access (in seconds since 1 Jan 1970)
16-19: time of last modification (in seconds since 1 Jan 1970)
20-23: time of last i-node change (in seconds since 1 Jan 1970)
24-27: number of first block in file
28-31: number of second block in file
32-35: number of third block in file
36-51: et cetera
52-55: number of indirect block in file
56-59: number of double indirect block in file
60-63: unused (reserved for enhanced versions)

Tracking free space


Linked list