File system implementation in OS

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 File system implementation :-

Numerous on-disk and in-memory configurations and structures are being used for implementing a file system. These structures differ based on the operating system and the file system but applying some general principles. Here they are portrayed below:
  • A boot control block usually contains the information required by the system for booting an operating system from that volume. When the disks do not contain any operating system, this block can be treated as empty. This is typically the first chunk of a volume. In UFS, this is termed as the boot block; in NTFS, it is the partition boot sector.
  • A volume control block holds volume or the partition details, such as the number of blocks in the partition, size of the blocks or chunks, free-block count along with free-block pointers. In UFS, it is termed as superblock; in NTFS, it is stored in the master file table.
  • A directory structure per file system is required for organizing the files. In UFS, it held the file names and associated 'inode' numbers. In NTFS, it gets stored in the master file table.
  • The FCB contains many details regarding any file which includes file permissions, ownership; the size of file and location of data blocks. In UFS, it is called the inode. In NTFS, this information gets stored within the master file table that uses a relational database (RDBM) structure, using a row per file.

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