Computer Systems: A Programmer's Perspective (3rd Edition)
3rd Edition
ISBN: 9780134092669
Author: Bryant, Randal E. Bryant, David R. O'Hallaron, David R., Randal E.; O'Hallaron, Bryant/O'hallaron
Publisher: PEARSON
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Chapter 8, Problem 8.23HW
One of your colleagues is thinking of using signals to allow a parent process to count events that occur in a child process. The idea is to notify the parent each time an event occurs by sending it a signal and letting the parent's signal handler increment a global counter variable, which the parent can then inspect after the child has terminated. However, when he runs the test program in Figure 8.45 on his system, he discovers that when the parent calls printf, counter always has a value of 2, even though the child has sent five signals to the parent. Perplexed, he comes to you for help. Can you explain the bug?
Figure 8.45 Counter program referenced in Problem 8-23.
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Chapter 8 Solutions
Computer Systems: A Programmer's Perspective (3rd Edition)
Ch. 8.2 - Prob. 8.1PPCh. 8.4 - Prob. 8.2PPCh. 8.4 - Prob. 8.3PPCh. 8.4 - Prob. 8.4PPCh. 8.4 - Practice Problem 8.5 (solution page 797) Write a...Ch. 8.4 - Practice Problem 8.6 (solution page 797) Write a...Ch. 8.5 - Practice Problem 8.7 (solution page 798) Write a...Ch. 8.5 - Prob. 8.8PPCh. 8 - Prob. 8.9HWCh. 8 - In this chapter, we have introduced some functions...
Ch. 8 - How many hello output lines does this program...Ch. 8 - How many "hello' output lines does this program...Ch. 8 - Prob. 8.13HWCh. 8 - How many hello output lines does this program...Ch. 8 - How many "hello lines does this program print?Ch. 8 - Prob. 8.16HWCh. 8 - Prob. 8.17HWCh. 8 - Consider the following program: Determine which of...Ch. 8 - How many lines of output does the following...Ch. 8 - Use execve to write a program called my1s whose...Ch. 8 - What are the possible output sequences from the...Ch. 8 - Write your own version of the Unix system function...Ch. 8 - One of your colleagues is thinking of using...Ch. 8 - Modify the program in Figure 8.18 so that the...Ch. 8 - Write a version of the fgets function, called...
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