Rixner Wrapup
Scott [e-mail]
Course Goals
Understand programming better
Linking Exceptions Memory I/O Networking
Prepare for systems classes
Computer architecture Compilers Operating systems Networking
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Introduction to Computer Systems
How does a computer system operate?
Hardware execution Operating system execution Run-time system execution Application execution
The best computer scientists understand the operation of a computer system at all of these levels
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COMP 320 Wrapup
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The C Language
Was this a course about C? Why use C? Are the system concepts we've learned about relevant to other application programming languages?
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COMP 320 Wrapup
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Course Topics
Machine-level representation of programs
Assembly to C
Linking and Virtual Memory
How does a program actually get loaded and run?
Exceptions
Critical events can happen outside your program
I/O, Networking, and Concurrency
Programs must communicate to be useful
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Linking
Libraries
What are they? How are they used by your program?
Incremental compilation
How can you minimize recompilation? How are 1000s of files combined into one program?
Errors
Why does your program compile but not run? Why does Windows tell you that "<blah>.dll is out of date"?
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Virtual Memory
Address spaces
What does a program's address space look like? How are programs loaded into memory? How are programs isolated and protected from each other? How do programs share memory?
Allocating memory
Where is your program's data stored? What if you need more memory? How is this allocation managed?
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Exceptional Control Flow
Running programs
What is a process, and how is it created? How does the shell work?
Communicating with a program
What happens when you type Ctrl-C, Ctrl-Z, etc.? How does your program find out about external events?
System calls
What happens to your program when you invoke the operating system?
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I/O, networking, and concurrency
I/O interface
How are files read, written, shared, etc.? Which I/O functions should you use and why?
Network access
Who manages the network? How can your program access the network?
Real programs
How does a web server How work? does a web client work?
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Course Perspective
Upper-level systems courses teach how systems work so you can build them
Computer architecture
How does a microprocessor work?
Compilers
How does a compiler work?
Operating systems
How does an operating system work?
Networking
How do network protocols work?
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Course Perspective
This course teaches how systems work so that you can use them
Purpose is to show how by knowing more about the underlying system, one can be more effective as a programmer Enable you to
Write programs that are more reliable and efficient Incorporate features that require hooks into OS
E.g., concurrency, signal handlers
Cover material in this course that you won't see elsewhere
It is difficult to build complex systems effectively if you do not know how they are going to be used!!!
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Final Exam
Take home exam Due on Monday, 12/18 at 5PM Open book, no computer
Yes: do you understand the concepts of the class? No: can you program them?
There will be programs on the exam
They will be short They will be in C Small amount of corresponding SPARC assembly
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Final Exam Policies
You must work on the exam during an uninterrupted period You may only consult the materials listed on the front page and nothing else Write yo...