HOMEWORK ASSIGNMENT 1
PROF: TOM WILKES FALL 2015 AKHILA DAMERA
1. What is the purpose of an interrupt?
Answer: An interrupt is a signal from software or hardware. It indicates the occurrence of an event. It may resume after interrupt handler finishes.
2 .What is a trap?
Answer: Trap is a synchronous interrupt caused by an exceptional condition. Like invalid memory access. A trap usually results in a switch to kernel mode, wherein the operating system performs some action before returning control to the originating process
3. How can multiprogramming
…show more content…
4.arg: A single argument that may be passed to start routine. It must be passed by reference as a pointer cast of type void. NULL may be used if no argument is to be passed.
21. What are the two other main thread libraries apart from the PThread library?
Answer: The two thread libraries which is involved in the process are
1 .Java thread 2 .Window thread
22. What are the three common models for mapping a user level thread to an operating system kernel thread? Answer: We have different models of threads used for mapping. Also we often use these types of models
1. Many to one model
2. one to one model
3 .Many too many model
Many To One: Many user-level threads mapped to single kernel thread
One To One: Each user-level thread maps to kernel thread
Many to Many: Multiples many user-level threads maps to a smaller kernel thread.
23. Using the program below, identify the values of pid that will be printed at
lines A, B, C, and D. (Assume that the actual pids of the parent and child are
9600 and 9750, respectively.)
#include