What are Open Files in Operating System:
Definition and Explanation:
The operating system usually maintains several lists for open files. There is a global list that contains references to open files all across the system for all processes. There is also a local list that maintains open files per process. Depending on the setup, these lists and data structures will contain:
File Pointer: The read/write pointer inside the file.
File Open Count: In the global table the system needs to maintain how many instances of this file are currently opened by various processes.
Disk location of the file: The hard drive location of the file is usually kept in memory to avoid having to read the hard drive to save something to a file.
Access Rights: Each file is opened in some access mode (read only/ etc.) An operating system can store this in a per-process open file table so that it can deny or allow some file operation on a per-process basis.
