OS-File Descriptor

A file descriptor or file control block is a control block containing information the system needs to manage a file. A typical file descri...

A file descriptor or file control block is a control block containing information the system needs to manage a file.

A typical file descriptor might include

1. symbolic file name
2. location of file in secondary storage
3. file organization (Sequential, indexed sequential, etc.)
4. device type
5. access control data
6. type (data file, object program, c source program, etc.)
7. disposition (permanent vs temporary)
8. creation date and time
9. destroy date
10. date and time last modified
11. access activity counts (number of reads, for example)

File descriptors are maintained on secondary storage. They are brought to primary storage when a file is opened.