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Review material from last lecture for midterm
Chapter 4: File Systems
Requirements
- Size: Store very large amounts of data
- Persistence: Data survives the creating process
- Access: Multiple processes can access the data concurrently
Solution: Store data in files that together form a file system
4.1: Files
4.1.1: File Naming
Very important. A major function of the filesystem.
- Does each file have a unique name?
Answer: Often no. We will discuss this below when we study
links.
- Extensions, e.g. the ``html'' in ``class-notes.html''
- Conventions just for humans: letter.teq (my convention)
- Conventions giving default behavior for some programs
- Emacs thinks .html files should be edited in html mode but can
edit them in any mode and can edit any file in html mode
- Netscape thinks .html means an html file but
<html> ... </html> works as well
- Gzip thinks .gz means a compresses file but accepts a
--suffix flag
- Required extensions for programs
- The gnu C compiler (and probably others) requires C
programs be named *.c and assembler programs be named *.s
- Required extensions by operating systems
- MS-DOS treats .com files specially
- I think windows 95 requires shortcuts to end in .lnk
- Case sensitive?