File systems Flashcards
What is a file system?
is a type ofdata storagewhich can be used to store, retrieve and update a set offiles
Different file systems have different attributes:
File structure and format
How a file is structured and recorded
File size and volume size
Total capacity of a disk
The maximum size of a single file
What are some popular types of file systems?
Windows: Fat32 exFat NTSF Linux: Ext 2,3,4 Lanyard Apple: HFS HFS Plus IBM-supercomputers:GPFS
What is a file?
File is an abstract data type
Contiguous logical space
But may be fragmented on a physical disk
What are the different types of files?
Text:notepad, html, program source
Binary: Image, Movie files also MS Word
Directory files
Special files - refer to a device
What are the different types of file operations:
Create – with new file name Write data At current location of the file Read data At current location of the file Reposition within file (seek) Move a pointer to a specific location of the file Delete Remove the whole file Truncate Cut some part of the file, remove some contents
What are the different types of Directory structure:
Single-level Directory
Two-level Directory
Tree-structured Directory
Graph-structured Directory
What is a single level directory
A single directory for all users
Has problem with “naming” and “grouping”
Names must be unique
Sub-directories not possible
What is a two level directory?
Separate directory for each user
What is a Tree-Structured Directories
Sub-directories become possible
What is a graph structured directory?
Graph-structure allows shared subdirectories and files
How are file shared across a distributed system?
Network File System (NFS)
a standard UNIX client-server file sharing protocol
What is disk mounting and demounting?
To attach a file system to a particular mount point (directory)
Demounting is used to detach the mounted disk
