linked list allocation

In linked allocation, a file is divided into blocks (just like other methods), but instead of storing them contiguously, the blocks can be scattered anywhere on the disk. These blocks are connected using a linked list, where each block contains:

  • The data
  • A pointer to the next block

The OS only stores the starting block address of the file. From there, it follows the pointers to access the entire file. Suppose a file F needs 4 blocks. Instead of storing them together, the OS may allocate:


To read the file: 
1. Start from first block
2. Read data
3. Follow pointer to next block
4. Repeat until NULL

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