What Is a File Control Block?
In order to access a file correctly, the operating system must set a data structure for the file to describe and control the file, which is called a "file control block (FCB)".
- Chinese name
- File control block
- Foreign name
- File Control Block
- Function
- Save file characteristic information
- English abbreviations
- FCB
- In order to access a file correctly, the operating system must set a data structure for the file to describe and control the file, which is called a "file control block (FCB)".
File control block meaning
- The file control block is a set of data structures with a fixed format set by the operating system for managing files. It stores all the attribute information (file attributes or metadata) required for managing files. [1]
File control block attribute
- The file control block should generally include the following file attribute information:
- 1. File mark and control information
- 2. File logical structure information
- 3. File physical structure information
- 4. File usage information
- 5. File Management Information
MS-DOS File Control Block File Control Block in MS-DOS
- In MS-DOS, ordinary file control blocks contain the following information:
- Drive letter, file name or device name, extension, current record number, record length, file length, date of creation or last modification, time of creation or last modification, DOS retention, current record number, relative record number.
- FCB has two types: "normal" and "extended". Extending FCB is to add 7 bytes of data in front of ordinary FCB. Among these 7 bytes, the first byte is -1, and the last byte indicates the file attribute , The remaining 5 bytes are 0. [2]